Commit 7912061226

Andrew Kelley <superjoe30@gmail.com>
2018-06-17 08:57:07
remove integer and float casting syntax
* add `@intCast` * add `@floatCast` * add `@floatToInt` * add `@intToFloat` See #1061
1 parent 06a26f0
doc/langref.html.in
@@ -1355,7 +1355,7 @@ var some_integers: [100]i32 = undefined;
 
 test "modify an array" {
     for (some_integers) |*item, i| {
-        item.* = i32(i);
+        item.* = @intCast(i32, i);
     }
     assert(some_integers[10] == 10);
     assert(some_integers[99] == 99);
@@ -1397,8 +1397,8 @@ var fancy_array = init: {
     var initial_value: [10]Point = undefined;
     for (initial_value) |*pt, i| {
         pt.* = Point{
-            .x = i32(i),
-            .y = i32(i) * 2,
+            .x = @intCast(i32, i),
+            .y = @intCast(i32, i) * 2,
         };
     }
     break :init initial_value;
@@ -2410,7 +2410,7 @@ test "for basics" {
     var sum2: i32 = 0;
     for (items) |value, i| {
         assert(@typeOf(i) == usize);
-        sum2 += i32(i);
+        sum2 += @intCast(i32, i);
     }
     assert(sum2 == 10);
 }
@@ -5730,7 +5730,7 @@ comptime {
       {#code_begin|test_err|attempt to cast negative value to unsigned integer#}
 comptime {
     const value: i32 = -1;
-    const unsigned = u32(value);
+    const unsigned = @intCast(u32, value);
 }
       {#code_end#}
       <p>At runtime crashes with the message <code>attempt to cast negative value to unsigned integer</code> and a stack trace.</p>
@@ -5744,7 +5744,7 @@ comptime {
       {#code_begin|test_err|cast from 'u16' to 'u8' truncates bits#}
 comptime {
     const spartan_count: u16 = 300;
-    const byte = u8(spartan_count);
+    const byte = @intCast(u8, spartan_count);
 }
       {#code_end#}
       <p>At runtime crashes with the message <code>integer cast truncated bits</code> and a stack trace.</p>
src/all_types.hpp
@@ -1357,6 +1357,10 @@ enum BuiltinFnId {
     BuiltinFnIdMod,
     BuiltinFnIdSqrt,
     BuiltinFnIdTruncate,
+    BuiltinFnIdIntCast,
+    BuiltinFnIdFloatCast,
+    BuiltinFnIdIntToFloat,
+    BuiltinFnIdFloatToInt,
     BuiltinFnIdIntType,
     BuiltinFnIdSetCold,
     BuiltinFnIdSetRuntimeSafety,
@@ -2040,6 +2044,10 @@ enum IrInstructionId {
     IrInstructionIdCmpxchg,
     IrInstructionIdFence,
     IrInstructionIdTruncate,
+    IrInstructionIdIntCast,
+    IrInstructionIdFloatCast,
+    IrInstructionIdIntToFloat,
+    IrInstructionIdFloatToInt,
     IrInstructionIdIntType,
     IrInstructionIdBoolNot,
     IrInstructionIdMemset,
@@ -2632,6 +2640,34 @@ struct IrInstructionTruncate {
     IrInstruction *target;
 };
 
+struct IrInstructionIntCast {
+    IrInstruction base;
+
+    IrInstruction *dest_type;
+    IrInstruction *target;
+};
+
+struct IrInstructionFloatCast {
+    IrInstruction base;
+
+    IrInstruction *dest_type;
+    IrInstruction *target;
+};
+
+struct IrInstructionIntToFloat {
+    IrInstruction base;
+
+    IrInstruction *dest_type;
+    IrInstruction *target;
+};
+
+struct IrInstructionFloatToInt {
+    IrInstruction base;
+
+    IrInstruction *dest_type;
+    IrInstruction *target;
+};
+
 struct IrInstructionIntType {
     IrInstruction base;
 
src/codegen.cpp
@@ -4722,6 +4722,10 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable,
         case IrInstructionIdPromiseResultType:
         case IrInstructionIdAwaitBookkeeping:
         case IrInstructionIdAddImplicitReturnType:
+        case IrInstructionIdIntCast:
+        case IrInstructionIdFloatCast:
+        case IrInstructionIdIntToFloat:
+        case IrInstructionIdFloatToInt:
             zig_unreachable();
 
         case IrInstructionIdReturn:
@@ -6310,6 +6314,10 @@ static void define_builtin_fns(CodeGen *g) {
     create_builtin_fn(g, BuiltinFnIdCmpxchgStrong, "cmpxchgStrong", 6);
     create_builtin_fn(g, BuiltinFnIdFence, "fence", 1);
     create_builtin_fn(g, BuiltinFnIdTruncate, "truncate", 2);
+    create_builtin_fn(g, BuiltinFnIdIntCast, "intCast", 2);
+    create_builtin_fn(g, BuiltinFnIdFloatCast, "floatCast", 2);
+    create_builtin_fn(g, BuiltinFnIdIntToFloat, "intToFloat", 2);
+    create_builtin_fn(g, BuiltinFnIdFloatToInt, "floatToInt", 2);
     create_builtin_fn(g, BuiltinFnIdCompileErr, "compileError", 1);
     create_builtin_fn(g, BuiltinFnIdCompileLog, "compileLog", SIZE_MAX);
     create_builtin_fn(g, BuiltinFnIdIntType, "IntType", 2); // TODO rename to Int
src/ir.cpp
@@ -460,6 +460,22 @@ static constexpr IrInstructionId ir_instruction_id(IrInstructionTruncate *) {
     return IrInstructionIdTruncate;
 }
 
+static constexpr IrInstructionId ir_instruction_id(IrInstructionIntCast *) {
+    return IrInstructionIdIntCast;
+}
+
+static constexpr IrInstructionId ir_instruction_id(IrInstructionFloatCast *) {
+    return IrInstructionIdFloatCast;
+}
+
+static constexpr IrInstructionId ir_instruction_id(IrInstructionIntToFloat *) {
+    return IrInstructionIdIntToFloat;
+}
+
+static constexpr IrInstructionId ir_instruction_id(IrInstructionFloatToInt *) {
+    return IrInstructionIdFloatToInt;
+}
+
 static constexpr IrInstructionId ir_instruction_id(IrInstructionIntType *) {
     return IrInstructionIdIntType;
 }
@@ -1899,10 +1915,48 @@ static IrInstruction *ir_build_truncate(IrBuilder *irb, Scope *scope, AstNode *s
     return &instruction->base;
 }
 
-static IrInstruction *ir_build_truncate_from(IrBuilder *irb, IrInstruction *old_instruction, IrInstruction *dest_type, IrInstruction *target) {
-    IrInstruction *new_instruction = ir_build_truncate(irb, old_instruction->scope, old_instruction->source_node, dest_type, target);
-    ir_link_new_instruction(new_instruction, old_instruction);
-    return new_instruction;
+static IrInstruction *ir_build_int_cast(IrBuilder *irb, Scope *scope, AstNode *source_node, IrInstruction *dest_type, IrInstruction *target) {
+    IrInstructionIntCast *instruction = ir_build_instruction<IrInstructionIntCast>(irb, scope, source_node);
+    instruction->dest_type = dest_type;
+    instruction->target = target;
+
+    ir_ref_instruction(dest_type, irb->current_basic_block);
+    ir_ref_instruction(target, irb->current_basic_block);
+
+    return &instruction->base;
+}
+
+static IrInstruction *ir_build_float_cast(IrBuilder *irb, Scope *scope, AstNode *source_node, IrInstruction *dest_type, IrInstruction *target) {
+    IrInstructionFloatCast *instruction = ir_build_instruction<IrInstructionFloatCast>(irb, scope, source_node);
+    instruction->dest_type = dest_type;
+    instruction->target = target;
+
+    ir_ref_instruction(dest_type, irb->current_basic_block);
+    ir_ref_instruction(target, irb->current_basic_block);
+
+    return &instruction->base;
+}
+
+static IrInstruction *ir_build_int_to_float(IrBuilder *irb, Scope *scope, AstNode *source_node, IrInstruction *dest_type, IrInstruction *target) {
+    IrInstructionIntToFloat *instruction = ir_build_instruction<IrInstructionIntToFloat>(irb, scope, source_node);
+    instruction->dest_type = dest_type;
+    instruction->target = target;
+
+    ir_ref_instruction(dest_type, irb->current_basic_block);
+    ir_ref_instruction(target, irb->current_basic_block);
+
+    return &instruction->base;
+}
+
+static IrInstruction *ir_build_float_to_int(IrBuilder *irb, Scope *scope, AstNode *source_node, IrInstruction *dest_type, IrInstruction *target) {
+    IrInstructionFloatToInt *instruction = ir_build_instruction<IrInstructionFloatToInt>(irb, scope, source_node);
+    instruction->dest_type = dest_type;
+    instruction->target = target;
+
+    ir_ref_instruction(dest_type, irb->current_basic_block);
+    ir_ref_instruction(target, irb->current_basic_block);
+
+    return &instruction->base;
 }
 
 static IrInstruction *ir_build_int_type(IrBuilder *irb, Scope *scope, AstNode *source_node, IrInstruction *is_signed, IrInstruction *bit_count) {
@@ -3957,6 +4011,66 @@ static IrInstruction *ir_gen_builtin_fn_call(IrBuilder *irb, Scope *scope, AstNo
                 IrInstruction *truncate = ir_build_truncate(irb, scope, node, arg0_value, arg1_value);
                 return ir_lval_wrap(irb, scope, truncate, lval);
             }
+        case BuiltinFnIdIntCast:
+            {
+                AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
+                IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope);
+                if (arg0_value == irb->codegen->invalid_instruction)
+                    return arg0_value;
+
+                AstNode *arg1_node = node->data.fn_call_expr.params.at(1);
+                IrInstruction *arg1_value = ir_gen_node(irb, arg1_node, scope);
+                if (arg1_value == irb->codegen->invalid_instruction)
+                    return arg1_value;
+
+                IrInstruction *result = ir_build_int_cast(irb, scope, node, arg0_value, arg1_value);
+                return ir_lval_wrap(irb, scope, result, lval);
+            }
+        case BuiltinFnIdFloatCast:
+            {
+                AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
+                IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope);
+                if (arg0_value == irb->codegen->invalid_instruction)
+                    return arg0_value;
+
+                AstNode *arg1_node = node->data.fn_call_expr.params.at(1);
+                IrInstruction *arg1_value = ir_gen_node(irb, arg1_node, scope);
+                if (arg1_value == irb->codegen->invalid_instruction)
+                    return arg1_value;
+
+                IrInstruction *result = ir_build_float_cast(irb, scope, node, arg0_value, arg1_value);
+                return ir_lval_wrap(irb, scope, result, lval);
+            }
+        case BuiltinFnIdIntToFloat:
+            {
+                AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
+                IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope);
+                if (arg0_value == irb->codegen->invalid_instruction)
+                    return arg0_value;
+
+                AstNode *arg1_node = node->data.fn_call_expr.params.at(1);
+                IrInstruction *arg1_value = ir_gen_node(irb, arg1_node, scope);
+                if (arg1_value == irb->codegen->invalid_instruction)
+                    return arg1_value;
+
+                IrInstruction *result = ir_build_int_to_float(irb, scope, node, arg0_value, arg1_value);
+                return ir_lval_wrap(irb, scope, result, lval);
+            }
+        case BuiltinFnIdFloatToInt:
+            {
+                AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
+                IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope);
+                if (arg0_value == irb->codegen->invalid_instruction)
+                    return arg0_value;
+
+                AstNode *arg1_node = node->data.fn_call_expr.params.at(1);
+                IrInstruction *arg1_value = ir_gen_node(irb, arg1_node, scope);
+                if (arg1_value == irb->codegen->invalid_instruction)
+                    return arg1_value;
+
+                IrInstruction *result = ir_build_float_to_int(irb, scope, node, arg0_value, arg1_value);
+                return ir_lval_wrap(irb, scope, result, lval);
+            }
         case BuiltinFnIdIntType:
             {
                 AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
@@ -9948,34 +10062,37 @@ static IrInstruction *ir_analyze_cast(IrAnalyze *ira, IrInstruction *source_inst
         return ir_resolve_cast(ira, source_instr, value, wanted_type, CastOpBoolToInt, false);
     }
 
-    // explicit widening or shortening cast
-    if ((wanted_type->id == TypeTableEntryIdInt &&
-        actual_type->id == TypeTableEntryIdInt) ||
-        (wanted_type->id == TypeTableEntryIdFloat &&
-        actual_type->id == TypeTableEntryIdFloat))
+    // explicit widening conversion
+    if (wanted_type->id == TypeTableEntryIdInt &&
+        actual_type->id == TypeTableEntryIdInt &&
+        wanted_type->data.integral.is_signed == actual_type->data.integral.is_signed &&
+        wanted_type->data.integral.bit_count >= actual_type->data.integral.bit_count)
     {
         return ir_analyze_widen_or_shorten(ira, source_instr, value, wanted_type);
     }
 
-    // explicit error set cast
-    if (wanted_type->id == TypeTableEntryIdErrorSet &&
-        actual_type->id == TypeTableEntryIdErrorSet)
+    // small enough unsigned ints can get casted to large enough signed ints
+    if (wanted_type->id == TypeTableEntryIdInt && wanted_type->data.integral.is_signed &&
+        actual_type->id == TypeTableEntryIdInt && !actual_type->data.integral.is_signed &&
+        wanted_type->data.integral.bit_count > actual_type->data.integral.bit_count)
     {
-        return ir_analyze_err_set_cast(ira, source_instr, value, wanted_type);
+        return ir_analyze_widen_or_shorten(ira, source_instr, value, wanted_type);
     }
 
-    // explicit cast from int to float
+    // explicit float widening conversion
     if (wanted_type->id == TypeTableEntryIdFloat &&
-        actual_type->id == TypeTableEntryIdInt)
+        actual_type->id == TypeTableEntryIdFloat &&
+        wanted_type->data.floating.bit_count >= actual_type->data.floating.bit_count)
     {
-        return ir_resolve_cast(ira, source_instr, value, wanted_type, CastOpIntToFloat, false);
+        return ir_analyze_widen_or_shorten(ira, source_instr, value, wanted_type);
     }
 
-    // explicit cast from float to int
-    if (wanted_type->id == TypeTableEntryIdInt &&
-        actual_type->id == TypeTableEntryIdFloat)
+
+    // explicit error set cast
+    if (wanted_type->id == TypeTableEntryIdErrorSet &&
+        actual_type->id == TypeTableEntryIdErrorSet)
     {
-        return ir_resolve_cast(ira, source_instr, value, wanted_type, CastOpFloatToInt, false);
+        return ir_analyze_err_set_cast(ira, source_instr, value, wanted_type);
     }
 
     // explicit cast from [N]T to []const T
@@ -17365,7 +17482,126 @@ static TypeTableEntry *ir_analyze_instruction_truncate(IrAnalyze *ira, IrInstruc
         return dest_type;
     }
 
-    ir_build_truncate_from(&ira->new_irb, &instruction->base, dest_type_value, target);
+    IrInstruction *new_instruction = ir_build_truncate(&ira->new_irb, instruction->base.scope,
+            instruction->base.source_node, dest_type_value, target);
+    ir_link_new_instruction(new_instruction, &instruction->base);
+    return dest_type;
+}
+
+static TypeTableEntry *ir_analyze_instruction_int_cast(IrAnalyze *ira, IrInstructionIntCast *instruction) {
+    TypeTableEntry *dest_type = ir_resolve_type(ira, instruction->dest_type->other);
+    if (type_is_invalid(dest_type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    if (dest_type->id != TypeTableEntryIdInt) {
+        ir_add_error(ira, instruction->dest_type, buf_sprintf("expected integer type, found '%s'", buf_ptr(&dest_type->name)));
+        return ira->codegen->builtin_types.entry_invalid;
+    }
+
+    IrInstruction *target = instruction->target->other;
+    if (type_is_invalid(target->value.type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    if (target->value.type->id == TypeTableEntryIdComptimeInt) {
+        if (ir_num_lit_fits_in_other_type(ira, target, dest_type, true)) {
+            IrInstruction *result = ir_resolve_cast(ira, &instruction->base, target, dest_type,
+                    CastOpNumLitToConcrete, false);
+            if (type_is_invalid(result->value.type))
+                return ira->codegen->builtin_types.entry_invalid;
+            ir_link_new_instruction(result, &instruction->base);
+            return dest_type;
+        } else {
+            return ira->codegen->builtin_types.entry_invalid;
+        }
+    }
+
+    if (target->value.type->id != TypeTableEntryIdInt) {
+        ir_add_error(ira, instruction->target, buf_sprintf("expected integer type, found '%s'",
+                    buf_ptr(&target->value.type->name)));
+        return ira->codegen->builtin_types.entry_invalid;
+    }
+
+    IrInstruction *result = ir_analyze_widen_or_shorten(ira, &instruction->base, target, dest_type);
+    if (type_is_invalid(result->value.type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    ir_link_new_instruction(result, &instruction->base);
+    return dest_type;
+}
+
+static TypeTableEntry *ir_analyze_instruction_float_cast(IrAnalyze *ira, IrInstructionFloatCast *instruction) {
+    TypeTableEntry *dest_type = ir_resolve_type(ira, instruction->dest_type->other);
+    if (type_is_invalid(dest_type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    if (dest_type->id != TypeTableEntryIdFloat) {
+        ir_add_error(ira, instruction->dest_type,
+                buf_sprintf("expected float type, found '%s'", buf_ptr(&dest_type->name)));
+        return ira->codegen->builtin_types.entry_invalid;
+    }
+
+    IrInstruction *target = instruction->target->other;
+    if (type_is_invalid(target->value.type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    if (target->value.type->id == TypeTableEntryIdComptimeInt ||
+        target->value.type->id == TypeTableEntryIdComptimeFloat)
+    {
+        if (ir_num_lit_fits_in_other_type(ira, target, dest_type, true)) {
+            CastOp op;
+            if (target->value.type->id == TypeTableEntryIdComptimeInt) {
+                op = CastOpIntToFloat;
+            } else {
+                op = CastOpNumLitToConcrete;
+            }
+            IrInstruction *result = ir_resolve_cast(ira, &instruction->base, target, dest_type, op, false);
+            if (type_is_invalid(result->value.type))
+                return ira->codegen->builtin_types.entry_invalid;
+            ir_link_new_instruction(result, &instruction->base);
+            return dest_type;
+        } else {
+            return ira->codegen->builtin_types.entry_invalid;
+        }
+    }
+
+    if (target->value.type->id != TypeTableEntryIdFloat) {
+        ir_add_error(ira, instruction->target, buf_sprintf("expected float type, found '%s'",
+                    buf_ptr(&target->value.type->name)));
+        return ira->codegen->builtin_types.entry_invalid;
+    }
+
+    IrInstruction *result = ir_analyze_widen_or_shorten(ira, &instruction->base, target, dest_type);
+    if (type_is_invalid(result->value.type))
+        return ira->codegen->builtin_types.entry_invalid;
+    ir_link_new_instruction(result, &instruction->base);
+    return dest_type;
+}
+
+static TypeTableEntry *ir_analyze_instruction_int_to_float(IrAnalyze *ira, IrInstructionIntToFloat *instruction) {
+    TypeTableEntry *dest_type = ir_resolve_type(ira, instruction->dest_type->other);
+    if (type_is_invalid(dest_type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    IrInstruction *target = instruction->target->other;
+    if (type_is_invalid(target->value.type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    IrInstruction *result = ir_resolve_cast(ira, &instruction->base, target, dest_type, CastOpIntToFloat, false);
+    ir_link_new_instruction(result, &instruction->base);
+    return dest_type;
+}
+
+static TypeTableEntry *ir_analyze_instruction_float_to_int(IrAnalyze *ira, IrInstructionFloatToInt *instruction) {
+    TypeTableEntry *dest_type = ir_resolve_type(ira, instruction->dest_type->other);
+    if (type_is_invalid(dest_type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    IrInstruction *target = instruction->target->other;
+    if (type_is_invalid(target->value.type))
+        return ira->codegen->builtin_types.entry_invalid;
+
+    IrInstruction *result = ir_resolve_cast(ira, &instruction->base, target, dest_type, CastOpFloatToInt, false);
+    ir_link_new_instruction(result, &instruction->base);
     return dest_type;
 }
 
@@ -19899,6 +20135,14 @@ static TypeTableEntry *ir_analyze_instruction_nocast(IrAnalyze *ira, IrInstructi
             return ir_analyze_instruction_fence(ira, (IrInstructionFence *)instruction);
         case IrInstructionIdTruncate:
             return ir_analyze_instruction_truncate(ira, (IrInstructionTruncate *)instruction);
+        case IrInstructionIdIntCast:
+            return ir_analyze_instruction_int_cast(ira, (IrInstructionIntCast *)instruction);
+        case IrInstructionIdFloatCast:
+            return ir_analyze_instruction_float_cast(ira, (IrInstructionFloatCast *)instruction);
+        case IrInstructionIdIntToFloat:
+            return ir_analyze_instruction_int_to_float(ira, (IrInstructionIntToFloat *)instruction);
+        case IrInstructionIdFloatToInt:
+            return ir_analyze_instruction_float_to_int(ira, (IrInstructionFloatToInt *)instruction);
         case IrInstructionIdIntType:
             return ir_analyze_instruction_int_type(ira, (IrInstructionIntType *)instruction);
         case IrInstructionIdBoolNot:
@@ -20242,6 +20486,10 @@ bool ir_has_side_effects(IrInstruction *instruction) {
         case IrInstructionIdPromiseResultType:
         case IrInstructionIdSqrt:
         case IrInstructionIdAtomicLoad:
+        case IrInstructionIdIntCast:
+        case IrInstructionIdFloatCast:
+        case IrInstructionIdIntToFloat:
+        case IrInstructionIdFloatToInt:
             return false;
 
         case IrInstructionIdAsm:
src/ir_print.cpp
@@ -648,6 +648,38 @@ static void ir_print_truncate(IrPrint *irp, IrInstructionTruncate *instruction)
     fprintf(irp->f, ")");
 }
 
+static void ir_print_int_cast(IrPrint *irp, IrInstructionIntCast *instruction) {
+    fprintf(irp->f, "@intCast(");
+    ir_print_other_instruction(irp, instruction->dest_type);
+    fprintf(irp->f, ", ");
+    ir_print_other_instruction(irp, instruction->target);
+    fprintf(irp->f, ")");
+}
+
+static void ir_print_float_cast(IrPrint *irp, IrInstructionFloatCast *instruction) {
+    fprintf(irp->f, "@floatCast(");
+    ir_print_other_instruction(irp, instruction->dest_type);
+    fprintf(irp->f, ", ");
+    ir_print_other_instruction(irp, instruction->target);
+    fprintf(irp->f, ")");
+}
+
+static void ir_print_int_to_float(IrPrint *irp, IrInstructionIntToFloat *instruction) {
+    fprintf(irp->f, "@intToFloat(");
+    ir_print_other_instruction(irp, instruction->dest_type);
+    fprintf(irp->f, ", ");
+    ir_print_other_instruction(irp, instruction->target);
+    fprintf(irp->f, ")");
+}
+
+static void ir_print_float_to_int(IrPrint *irp, IrInstructionFloatToInt *instruction) {
+    fprintf(irp->f, "@floatToInt(");
+    ir_print_other_instruction(irp, instruction->dest_type);
+    fprintf(irp->f, ", ");
+    ir_print_other_instruction(irp, instruction->target);
+    fprintf(irp->f, ")");
+}
+
 static void ir_print_int_type(IrPrint *irp, IrInstructionIntType *instruction) {
     fprintf(irp->f, "@IntType(");
     ir_print_other_instruction(irp, instruction->is_signed);
@@ -1417,6 +1449,18 @@ static void ir_print_instruction(IrPrint *irp, IrInstruction *instruction) {
         case IrInstructionIdTruncate:
             ir_print_truncate(irp, (IrInstructionTruncate *)instruction);
             break;
+        case IrInstructionIdIntCast:
+            ir_print_int_cast(irp, (IrInstructionIntCast *)instruction);
+            break;
+        case IrInstructionIdFloatCast:
+            ir_print_float_cast(irp, (IrInstructionFloatCast *)instruction);
+            break;
+        case IrInstructionIdIntToFloat:
+            ir_print_int_to_float(irp, (IrInstructionIntToFloat *)instruction);
+            break;
+        case IrInstructionIdFloatToInt:
+            ir_print_float_to_int(irp, (IrInstructionFloatToInt *)instruction);
+            break;
         case IrInstructionIdIntType:
             ir_print_int_type(irp, (IrInstructionIntType *)instruction);
             break;
src/main.cpp
@@ -34,7 +34,7 @@ static int usage(const char *arg0) {
         "  --assembly [source]          add assembly file to build\n"
         "  --cache-dir [path]           override the cache directory\n"
         "  --color [auto|off|on]        enable or disable colored error messages\n"
-        "  --emit [filetype]            emit a specific file format as compilation output\n"
+        "  --emit [asm|bin|llvm-ir]     emit a specific file format as compilation output\n"
         "  --enable-timing-info         print timing diagnostics\n"
         "  --libc-include-dir [path]    directory where libc stdlib.h resides\n"
         "  --name [name]                override output name\n"
std/crypto/blake2.zig
@@ -79,7 +79,7 @@ fn Blake2s(comptime out_len: usize) type {
             mem.copy(u32, d.h[0..], iv[0..]);
 
             // No key plus default parameters
-            d.h[0] ^= 0x01010000 ^ u32(out_len >> 3);
+            d.h[0] ^= 0x01010000 ^ @intCast(u32, out_len >> 3);
             d.t = 0;
             d.buf_len = 0;
         }
@@ -110,7 +110,7 @@ fn Blake2s(comptime out_len: usize) type {
 
             // Copy any remainder for next pass.
             mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-            d.buf_len += u8(b[off..].len);
+            d.buf_len += @intCast(u8, b[off..].len);
         }
 
         pub fn final(d: *Self, out: []u8) void {
@@ -144,7 +144,7 @@ fn Blake2s(comptime out_len: usize) type {
             }
 
             v[12] ^= @truncate(u32, d.t);
-            v[13] ^= u32(d.t >> 32);
+            v[13] ^= @intCast(u32, d.t >> 32);
             if (last) v[14] = ~v[14];
 
             const rounds = comptime []RoundParam{
@@ -345,7 +345,7 @@ fn Blake2b(comptime out_len: usize) type {
 
             // Copy any remainder for next pass.
             mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-            d.buf_len += u8(b[off..].len);
+            d.buf_len += @intCast(u8, b[off..].len);
         }
 
         pub fn final(d: *Self, out: []u8) void {
@@ -377,7 +377,7 @@ fn Blake2b(comptime out_len: usize) type {
             }
 
             v[12] ^= @truncate(u64, d.t);
-            v[13] ^= u64(d.t >> 64);
+            v[13] ^= @intCast(u64, d.t >> 64);
             if (last) v[14] = ~v[14];
 
             const rounds = comptime []RoundParam{
std/crypto/md5.zig
@@ -78,7 +78,7 @@ pub const Md5 = struct {
 
         // Copy any remainder for next pass.
         mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-        d.buf_len += u8(b[off..].len);
+        d.buf_len += @intCast(u8, b[off..].len);
 
         // Md5 uses the bottom 64-bits for length padding
         d.total_len +%= b.len;
@@ -103,9 +103,9 @@ pub const Md5 = struct {
         // Append message length.
         var i: usize = 1;
         var len = d.total_len >> 5;
-        d.buf[56] = u8(d.total_len & 0x1f) << 3;
+        d.buf[56] = @intCast(u8, d.total_len & 0x1f) << 3;
         while (i < 8) : (i += 1) {
-            d.buf[56 + i] = u8(len & 0xff);
+            d.buf[56 + i] = @intCast(u8, len & 0xff);
             len >>= 8;
         }
 
std/crypto/sha1.zig
@@ -78,7 +78,7 @@ pub const Sha1 = struct {
 
         // Copy any remainder for next pass.
         mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-        d.buf_len += u8(b[off..].len);
+        d.buf_len += @intCast(u8, b[off..].len);
 
         d.total_len += b.len;
     }
@@ -102,9 +102,9 @@ pub const Sha1 = struct {
         // Append message length.
         var i: usize = 1;
         var len = d.total_len >> 5;
-        d.buf[63] = u8(d.total_len & 0x1f) << 3;
+        d.buf[63] = @intCast(u8, d.total_len & 0x1f) << 3;
         while (i < 8) : (i += 1) {
-            d.buf[63 - i] = u8(len & 0xff);
+            d.buf[63 - i] = @intCast(u8, len & 0xff);
             len >>= 8;
         }
 
std/crypto/sha2.zig
@@ -131,7 +131,7 @@ fn Sha2_32(comptime params: Sha2Params32) type {
 
             // Copy any remainder for next pass.
             mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-            d.buf_len += u8(b[off..].len);
+            d.buf_len += @intCast(u8, b[off..].len);
 
             d.total_len += b.len;
         }
@@ -155,9 +155,9 @@ fn Sha2_32(comptime params: Sha2Params32) type {
             // Append message length.
             var i: usize = 1;
             var len = d.total_len >> 5;
-            d.buf[63] = u8(d.total_len & 0x1f) << 3;
+            d.buf[63] = @intCast(u8, d.total_len & 0x1f) << 3;
             while (i < 8) : (i += 1) {
-                d.buf[63 - i] = u8(len & 0xff);
+                d.buf[63 - i] = @intCast(u8, len & 0xff);
                 len >>= 8;
             }
 
@@ -472,7 +472,7 @@ fn Sha2_64(comptime params: Sha2Params64) type {
 
             // Copy any remainder for next pass.
             mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-            d.buf_len += u8(b[off..].len);
+            d.buf_len += @intCast(u8, b[off..].len);
 
             d.total_len += b.len;
         }
@@ -496,9 +496,9 @@ fn Sha2_64(comptime params: Sha2Params64) type {
             // Append message length.
             var i: usize = 1;
             var len = d.total_len >> 5;
-            d.buf[127] = u8(d.total_len & 0x1f) << 3;
+            d.buf[127] = @intCast(u8, d.total_len & 0x1f) << 3;
             while (i < 16) : (i += 1) {
-                d.buf[127 - i] = u8(len & 0xff);
+                d.buf[127 - i] = @intCast(u8, len & 0xff);
                 len >>= 8;
             }
 
std/debug/index.zig
@@ -554,7 +554,7 @@ const LineNumberProgram = struct {
             const file_name = try os.path.join(self.file_entries.allocator, dir_name, file_entry.file_name);
             errdefer self.file_entries.allocator.free(file_name);
             return LineInfo{
-                .line = if (self.prev_line >= 0) usize(self.prev_line) else 0,
+                .line = if (self.prev_line >= 0) @intCast(usize, self.prev_line) else 0,
                 .column = self.prev_column,
                 .file_name = file_name,
                 .allocator = self.file_entries.allocator,
@@ -1070,7 +1070,7 @@ fn readULeb128(in_stream: var) !u64 {
 
         var operand: u64 = undefined;
 
-        if (@shlWithOverflow(u64, byte & 0b01111111, u6(shift), &operand)) return error.InvalidDebugInfo;
+        if (@shlWithOverflow(u64, byte & 0b01111111, @intCast(u6, shift), &operand)) return error.InvalidDebugInfo;
 
         result |= operand;
 
@@ -1089,13 +1089,13 @@ fn readILeb128(in_stream: var) !i64 {
 
         var operand: i64 = undefined;
 
-        if (@shlWithOverflow(i64, byte & 0b01111111, u6(shift), &operand)) return error.InvalidDebugInfo;
+        if (@shlWithOverflow(i64, byte & 0b01111111, @intCast(u6, shift), &operand)) return error.InvalidDebugInfo;
 
         result |= operand;
         shift += 7;
 
         if ((byte & 0b10000000) == 0) {
-            if (shift < @sizeOf(i64) * 8 and (byte & 0b01000000) != 0) result |= -(i64(1) << u6(shift));
+            if (shift < @sizeOf(i64) * 8 and (byte & 0b01000000) != 0) result |= -(i64(1) << @intCast(u6, shift));
             return result;
         }
     }
std/fmt/errol/index.zig
@@ -29,11 +29,11 @@ pub fn roundToPrecision(float_decimal: *FloatDecimal, precision: usize, mode: Ro
     switch (mode) {
         RoundMode.Decimal => {
             if (float_decimal.exp >= 0) {
-                round_digit = precision + usize(float_decimal.exp);
+                round_digit = precision + @intCast(usize, float_decimal.exp);
             } else {
                 // if a small negative exp, then adjust we need to offset by the number
                 // of leading zeros that will occur.
-                const min_exp_required = usize(-float_decimal.exp);
+                const min_exp_required = @intCast(usize, -float_decimal.exp);
                 if (precision > min_exp_required) {
                     round_digit = precision - min_exp_required;
                 }
@@ -107,16 +107,16 @@ fn errol3u(val: f64, buffer: []u8) FloatDecimal {
     // normalize the midpoint
 
     const e = math.frexp(val).exponent;
-    var exp = i16(math.floor(307 + f64(e) * 0.30103));
+    var exp = @floatToInt(i16, math.floor(307 + @intToFloat(f64, e) * 0.30103));
     if (exp < 20) {
         exp = 20;
-    } else if (usize(exp) >= lookup_table.len) {
-        exp = i16(lookup_table.len - 1);
+    } else if (@intCast(usize, exp) >= lookup_table.len) {
+        exp = @intCast(i16, lookup_table.len - 1);
     }
 
-    var mid = lookup_table[usize(exp)];
+    var mid = lookup_table[@intCast(usize, exp)];
     mid = hpProd(mid, val);
-    const lten = lookup_table[usize(exp)].val;
+    const lten = lookup_table[@intCast(usize, exp)].val;
 
     exp -= 307;
 
@@ -168,25 +168,25 @@ fn errol3u(val: f64, buffer: []u8) FloatDecimal {
     // the 0-index for this extra digit.
     var buf_index: usize = 1;
     while (true) {
-        var hdig = u8(math.floor(high.val));
-        if ((high.val == f64(hdig)) and (high.off < 0)) hdig -= 1;
+        var hdig = @floatToInt(u8, math.floor(high.val));
+        if ((high.val == @intToFloat(f64, hdig)) and (high.off < 0)) hdig -= 1;
 
-        var ldig = u8(math.floor(low.val));
-        if ((low.val == f64(ldig)) and (low.off < 0)) ldig -= 1;
+        var ldig = @floatToInt(u8, math.floor(low.val));
+        if ((low.val == @intToFloat(f64, ldig)) and (low.off < 0)) ldig -= 1;
 
         if (ldig != hdig) break;
 
         buffer[buf_index] = hdig + '0';
         buf_index += 1;
-        high.val -= f64(hdig);
-        low.val -= f64(ldig);
+        high.val -= @intToFloat(f64, hdig);
+        low.val -= @intToFloat(f64, ldig);
         hpMul10(&high);
         hpMul10(&low);
     }
 
     const tmp = (high.val + low.val) / 2.0;
-    var mdig = u8(math.floor(tmp + 0.5));
-    if ((f64(mdig) - tmp) == 0.5 and (mdig & 0x1) != 0) mdig -= 1;
+    var mdig = @floatToInt(u8, math.floor(tmp + 0.5));
+    if ((@intToFloat(f64, mdig) - tmp) == 0.5 and (mdig & 0x1) != 0) mdig -= 1;
 
     buffer[buf_index] = mdig + '0';
     buf_index += 1;
@@ -304,7 +304,7 @@ fn errolInt(val: f64, buffer: []u8) FloatDecimal {
 
     assert((val > 9.007199254740992e15) and val < (3.40282366920938e38));
 
-    var mid = u128(val);
+    var mid = @floatToInt(u128, val);
     var low: u128 = mid - fpeint((fpnext(val) - val) / 2.0);
     var high: u128 = mid + fpeint((val - fpprev(val)) / 2.0);
 
@@ -314,11 +314,11 @@ fn errolInt(val: f64, buffer: []u8) FloatDecimal {
         low -= 1;
     }
 
-    var l64 = u64(low % pow19);
-    const lf = u64((low / pow19) % pow19);
+    var l64 = @intCast(u64, low % pow19);
+    const lf = @intCast(u64, (low / pow19) % pow19);
 
-    var h64 = u64(high % pow19);
-    const hf = u64((high / pow19) % pow19);
+    var h64 = @intCast(u64, high % pow19);
+    const hf = @intCast(u64, (high / pow19) % pow19);
 
     if (lf != hf) {
         l64 = lf;
@@ -348,7 +348,7 @@ fn errolInt(val: f64, buffer: []u8) FloatDecimal {
 
     return FloatDecimal{
         .digits = buffer[0..buf_index],
-        .exp = i32(buf_index) + mi,
+        .exp = @intCast(i32, buf_index) + mi,
     };
 }
 
@@ -359,33 +359,33 @@ fn errolInt(val: f64, buffer: []u8) FloatDecimal {
 fn errolFixed(val: f64, buffer: []u8) FloatDecimal {
     assert((val >= 16.0) and (val < 9.007199254740992e15));
 
-    const u = u64(val);
-    const n = f64(u);
+    const u = @floatToInt(u64, val);
+    const n = @intToFloat(f64, u);
 
     var mid = val - n;
     var lo = ((fpprev(val) - n) + mid) / 2.0;
     var hi = ((fpnext(val) - n) + mid) / 2.0;
 
     var buf_index = u64toa(u, buffer);
-    var exp = i32(buf_index);
+    var exp = @intCast(i32, buf_index);
     var j = buf_index;
     buffer[j] = 0;
 
     if (mid != 0.0) {
         while (mid != 0.0) {
             lo *= 10.0;
-            const ldig = i32(lo);
-            lo -= f64(ldig);
+            const ldig = @floatToInt(i32, lo);
+            lo -= @intToFloat(f64, ldig);
 
             mid *= 10.0;
-            const mdig = i32(mid);
-            mid -= f64(mdig);
+            const mdig = @floatToInt(i32, mid);
+            mid -= @intToFloat(f64, mdig);
 
             hi *= 10.0;
-            const hdig = i32(hi);
-            hi -= f64(hdig);
+            const hdig = @floatToInt(i32, hi);
+            hi -= @intToFloat(f64, hdig);
 
-            buffer[j] = u8(mdig + '0');
+            buffer[j] = @intCast(u8, mdig + '0');
             j += 1;
 
             if (hdig != ldig or j > 50) break;
@@ -452,7 +452,7 @@ fn u64toa(value_param: u64, buffer: []u8) usize {
     var buf_index: usize = 0;
 
     if (value < kTen8) {
-        const v = u32(value);
+        const v = @intCast(u32, value);
         if (v < 10000) {
             const d1: u32 = (v / 100) << 1;
             const d2: u32 = (v % 100) << 1;
@@ -507,8 +507,8 @@ fn u64toa(value_param: u64, buffer: []u8) usize {
             buf_index += 1;
         }
     } else if (value < kTen16) {
-        const v0: u32 = u32(value / kTen8);
-        const v1: u32 = u32(value % kTen8);
+        const v0: u32 = @intCast(u32, value / kTen8);
+        const v1: u32 = @intCast(u32, value % kTen8);
 
         const b0: u32 = v0 / 10000;
         const c0: u32 = v0 % 10000;
@@ -578,11 +578,11 @@ fn u64toa(value_param: u64, buffer: []u8) usize {
         buffer[buf_index] = c_digits_lut[d8 + 1];
         buf_index += 1;
     } else {
-        const a = u32(value / kTen16); // 1 to 1844
+        const a = @intCast(u32, value / kTen16); // 1 to 1844
         value %= kTen16;
 
         if (a < 10) {
-            buffer[buf_index] = '0' + u8(a);
+            buffer[buf_index] = '0' + @intCast(u8, a);
             buf_index += 1;
         } else if (a < 100) {
             const i: u32 = a << 1;
@@ -591,7 +591,7 @@ fn u64toa(value_param: u64, buffer: []u8) usize {
             buffer[buf_index] = c_digits_lut[i + 1];
             buf_index += 1;
         } else if (a < 1000) {
-            buffer[buf_index] = '0' + u8(a / 100);
+            buffer[buf_index] = '0' + @intCast(u8, a / 100);
             buf_index += 1;
 
             const i: u32 = (a % 100) << 1;
@@ -612,8 +612,8 @@ fn u64toa(value_param: u64, buffer: []u8) usize {
             buf_index += 1;
         }
 
-        const v0 = u32(value / kTen8);
-        const v1 = u32(value % kTen8);
+        const v0 = @intCast(u32, value / kTen8);
+        const v1 = @intCast(u32, value % kTen8);
 
         const b0: u32 = v0 / 10000;
         const c0: u32 = v0 % 10000;
std/fmt/index.zig
@@ -5,6 +5,7 @@ const assert = debug.assert;
 const mem = std.mem;
 const builtin = @import("builtin");
 const errol = @import("errol/index.zig");
+const lossyCast = std.math.lossyCast;
 
 const max_int_digits = 65;
 
@@ -463,7 +464,7 @@ pub fn formatFloatDecimal(
         errol.roundToPrecision(&float_decimal, precision, errol.RoundMode.Decimal);
 
         // exp < 0 means the leading is always 0 as errol result is normalized.
-        var num_digits_whole = if (float_decimal.exp > 0) usize(float_decimal.exp) else 0;
+        var num_digits_whole = if (float_decimal.exp > 0) @intCast(usize, float_decimal.exp) else 0;
 
         // the actual slice into the buffer, we may need to zero-pad between num_digits_whole and this.
         var num_digits_whole_no_pad = math.min(num_digits_whole, float_decimal.digits.len);
@@ -492,7 +493,7 @@ pub fn formatFloatDecimal(
 
         // Zero-fill until we reach significant digits or run out of precision.
         if (float_decimal.exp <= 0) {
-            const zero_digit_count = usize(-float_decimal.exp);
+            const zero_digit_count = @intCast(usize, -float_decimal.exp);
             const zeros_to_print = math.min(zero_digit_count, precision);
 
             var i: usize = 0;
@@ -521,7 +522,7 @@ pub fn formatFloatDecimal(
         }
     } else {
         // exp < 0 means the leading is always 0 as errol result is normalized.
-        var num_digits_whole = if (float_decimal.exp > 0) usize(float_decimal.exp) else 0;
+        var num_digits_whole = if (float_decimal.exp > 0) @intCast(usize, float_decimal.exp) else 0;
 
         // the actual slice into the buffer, we may need to zero-pad between num_digits_whole and this.
         var num_digits_whole_no_pad = math.min(num_digits_whole, float_decimal.digits.len);
@@ -547,7 +548,7 @@ pub fn formatFloatDecimal(
 
         // Zero-fill until we reach significant digits or run out of precision.
         if (float_decimal.exp < 0) {
-            const zero_digit_count = usize(-float_decimal.exp);
+            const zero_digit_count = @intCast(usize, -float_decimal.exp);
 
             var i: usize = 0;
             while (i < zero_digit_count) : (i += 1) {
@@ -578,7 +579,7 @@ pub fn formatBytes(
         1024 => math.min(math.log2(value) / 10, mags_iec.len - 1),
         else => unreachable,
     };
-    const new_value = f64(value) / math.pow(f64, f64(radix), f64(magnitude));
+    const new_value = lossyCast(f64, value) / math.pow(f64, lossyCast(f64, radix), lossyCast(f64, magnitude));
     const suffix = switch (radix) {
         1000 => mags_si[magnitude],
         1024 => mags_iec[magnitude],
@@ -628,15 +629,15 @@ fn formatIntSigned(
     if (value < 0) {
         const minus_sign: u8 = '-';
         try output(context, (*[1]u8)(&minus_sign)[0..]);
-        const new_value = uint(-(value + 1)) + 1;
+        const new_value = @intCast(uint, -(value + 1)) + 1;
         const new_width = if (width == 0) 0 else (width - 1);
         return formatIntUnsigned(new_value, base, uppercase, new_width, context, Errors, output);
     } else if (width == 0) {
-        return formatIntUnsigned(uint(value), base, uppercase, width, context, Errors, output);
+        return formatIntUnsigned(@intCast(uint, value), base, uppercase, width, context, Errors, output);
     } else {
         const plus_sign: u8 = '+';
         try output(context, (*[1]u8)(&plus_sign)[0..]);
-        const new_value = uint(value);
+        const new_value = @intCast(uint, value);
         const new_width = if (width == 0) 0 else (width - 1);
         return formatIntUnsigned(new_value, base, uppercase, new_width, context, Errors, output);
     }
@@ -660,7 +661,7 @@ fn formatIntUnsigned(
     while (true) {
         const digit = a % base;
         index -= 1;
-        buf[index] = digitToChar(u8(digit), uppercase);
+        buf[index] = digitToChar(@intCast(u8, digit), uppercase);
         a /= base;
         if (a == 0) break;
     }
std/hash/crc.zig
@@ -26,7 +26,7 @@ pub fn Crc32WithPoly(comptime poly: u32) type {
             var tables: [8][256]u32 = undefined;
 
             for (tables[0]) |*e, i| {
-                var crc = u32(i);
+                var crc = @intCast(u32, i);
                 var j: usize = 0;
                 while (j < 8) : (j += 1) {
                     if (crc & 1 == 1) {
@@ -122,7 +122,7 @@ pub fn Crc32SmallWithPoly(comptime poly: u32) type {
             var table: [16]u32 = undefined;
 
             for (table) |*e, i| {
-                var crc = u32(i * 16);
+                var crc = @intCast(u32, i * 16);
                 var j: usize = 0;
                 while (j < 8) : (j += 1) {
                     if (crc & 1 == 1) {
std/hash/siphash.zig
@@ -81,7 +81,7 @@ fn SipHash(comptime T: type, comptime c_rounds: usize, comptime d_rounds: usize)
 
             // Remainder for next pass.
             mem.copy(u8, d.buf[d.buf_len..], b[off..]);
-            d.buf_len += u8(b[off..].len);
+            d.buf_len += @intCast(u8, b[off..].len);
             d.msg_len +%= @truncate(u8, b.len);
         }
 
@@ -233,7 +233,7 @@ test "siphash64-2-4 sanity" {
 
     var buffer: [64]u8 = undefined;
     for (vectors) |vector, i| {
-        buffer[i] = u8(i);
+        buffer[i] = @intCast(u8, i);
 
         const expected = mem.readInt(vector, u64, Endian.Little);
         debug.assert(siphash.hash(test_key, buffer[0..i]) == expected);
@@ -312,7 +312,7 @@ test "siphash128-2-4 sanity" {
 
     var buffer: [64]u8 = undefined;
     for (vectors) |vector, i| {
-        buffer[i] = u8(i);
+        buffer[i] = @intCast(u8, i);
 
         const expected = mem.readInt(vector, u128, Endian.Little);
         debug.assert(siphash.hash(test_key, buffer[0..i]) == expected);
std/math/big/int.zig
@@ -135,7 +135,7 @@ pub const Int = struct {
                 self.positive = value >= 0;
                 self.len = 0;
 
-                var w_value: UT = if (value < 0) UT(-value) else UT(value);
+                var w_value: UT = if (value < 0) @intCast(UT, -value) else @intCast(UT, value);
 
                 if (info.bits <= Limb.bit_count) {
                     self.limbs[0] = Limb(w_value);
@@ -198,7 +198,7 @@ pub const Int = struct {
                 var r: UT = 0;
 
                 if (@sizeOf(UT) <= @sizeOf(Limb)) {
-                    r = UT(self.limbs[0]);
+                    r = @intCast(UT, self.limbs[0]);
                 } else {
                     for (self.limbs[0..self.len]) |_, ri| {
                         const limb = self.limbs[self.len - ri - 1];
@@ -210,7 +210,7 @@ pub const Int = struct {
                 if (!T.is_signed) {
                     return if (self.positive) r else error.NegativeIntoUnsigned;
                 } else {
-                    return if (self.positive) T(r) else -T(r);
+                    return if (self.positive) @intCast(T, r) else -@intCast(T, r);
                 }
             },
             else => {
@@ -295,7 +295,7 @@ pub const Int = struct {
             for (self.limbs[0..self.len]) |limb| {
                 var shift: usize = 0;
                 while (shift < Limb.bit_count) : (shift += base_shift) {
-                    const r = u8((limb >> Log2Limb(shift)) & Limb(base - 1));
+                    const r = @intCast(u8, (limb >> @intCast(Log2Limb, shift)) & Limb(base - 1));
                     const ch = try digitToChar(r, base);
                     try digits.append(ch);
                 }
@@ -329,7 +329,7 @@ pub const Int = struct {
                 var r_word = r.limbs[0];
                 var i: usize = 0;
                 while (i < digits_per_limb) : (i += 1) {
-                    const ch = try digitToChar(u8(r_word % base), base);
+                    const ch = try digitToChar(@intCast(u8, r_word % base), base);
                     r_word /= base;
                     try digits.append(ch);
                 }
@@ -340,7 +340,7 @@ pub const Int = struct {
 
                 var r_word = q.limbs[0];
                 while (r_word != 0) {
-                    const ch = try digitToChar(u8(r_word % base), base);
+                    const ch = try digitToChar(@intCast(u8, r_word % base), base);
                     r_word /= base;
                     try digits.append(ch);
                 }
@@ -801,7 +801,7 @@ pub const Int = struct {
                 q.limbs[i - t - 1] = @maxValue(Limb);
             } else {
                 const num = (DoubleLimb(x.limbs[i]) << Limb.bit_count) | DoubleLimb(x.limbs[i - 1]);
-                const z = Limb(num / DoubleLimb(y.limbs[t]));
+                const z = @intCast(Limb, num / DoubleLimb(y.limbs[t]));
                 q.limbs[i - t - 1] = if (z > @maxValue(Limb)) @maxValue(Limb) else Limb(z);
             }
 
@@ -860,7 +860,7 @@ pub const Int = struct {
         debug.assert(r.len >= a.len + (shift / Limb.bit_count) + 1);
 
         const limb_shift = shift / Limb.bit_count + 1;
-        const interior_limb_shift = Log2Limb(shift % Limb.bit_count);
+        const interior_limb_shift = @intCast(Log2Limb, shift % Limb.bit_count);
 
         var carry: Limb = 0;
         var i: usize = 0;
@@ -869,7 +869,7 @@ pub const Int = struct {
             const dst_i = src_i + limb_shift;
 
             const src_digit = a[src_i];
-            r[dst_i] = carry | @inlineCall(math.shr, Limb, src_digit, Limb.bit_count - Limb(interior_limb_shift));
+            r[dst_i] = carry | @inlineCall(math.shr, Limb, src_digit, Limb.bit_count - @intCast(Limb, interior_limb_shift));
             carry = (src_digit << interior_limb_shift);
         }
 
@@ -898,7 +898,7 @@ pub const Int = struct {
         debug.assert(r.len >= a.len - (shift / Limb.bit_count));
 
         const limb_shift = shift / Limb.bit_count;
-        const interior_limb_shift = Log2Limb(shift % Limb.bit_count);
+        const interior_limb_shift = @intCast(Log2Limb, shift % Limb.bit_count);
 
         var carry: Limb = 0;
         var i: usize = 0;
@@ -908,7 +908,7 @@ pub const Int = struct {
 
             const src_digit = a[src_i];
             r[dst_i] = carry | (src_digit >> interior_limb_shift);
-            carry = @inlineCall(math.shl, Limb, src_digit, Limb.bit_count - Limb(interior_limb_shift));
+            carry = @inlineCall(math.shl, Limb, src_digit, Limb.bit_count - @intCast(Limb, interior_limb_shift));
         }
     }
 
std/math/complex/atan.zig
@@ -4,7 +4,7 @@ const math = std.math;
 const cmath = math.complex;
 const Complex = cmath.Complex;
 
-pub fn atan(z: var) Complex(@typeOf(z.re)) {
+pub fn atan(z: var) @typeOf(z) {
     const T = @typeOf(z.re);
     return switch (T) {
         f32 => atan32(z),
@@ -25,11 +25,11 @@ fn redupif32(x: f32) f32 {
         t -= 0.5;
     }
 
-    const u = f32(i32(t));
+    const u = @intToFloat(f32, @floatToInt(i32, t));
     return ((x - u * DP1) - u * DP2) - t * DP3;
 }
 
-fn atan32(z: *const Complex(f32)) Complex(f32) {
+fn atan32(z: Complex(f32)) Complex(f32) {
     const maxnum = 1.0e38;
 
     const x = z.re;
@@ -74,11 +74,11 @@ fn redupif64(x: f64) f64 {
         t -= 0.5;
     }
 
-    const u = f64(i64(t));
+    const u = @intToFloat(f64, @floatToInt(i64, t));
     return ((x - u * DP1) - u * DP2) - t * DP3;
 }
 
-fn atan64(z: *const Complex(f64)) Complex(f64) {
+fn atan64(z: Complex(f64)) Complex(f64) {
     const maxnum = 1.0e308;
 
     const x = z.re;
std/math/complex/cosh.zig
@@ -83,12 +83,12 @@ fn cosh64(z: *const Complex(f64)) Complex(f64) {
     const y = z.im;
 
     const fx = @bitCast(u64, x);
-    const hx = u32(fx >> 32);
+    const hx = @intCast(u32, fx >> 32);
     const lx = @truncate(u32, fx);
     const ix = hx & 0x7fffffff;
 
     const fy = @bitCast(u64, y);
-    const hy = u32(fy >> 32);
+    const hy = @intCast(u32, fy >> 32);
     const ly = @truncate(u32, fy);
     const iy = hy & 0x7fffffff;
 
std/math/complex/exp.zig
@@ -6,7 +6,7 @@ const Complex = cmath.Complex;
 
 const ldexp_cexp = @import("ldexp.zig").ldexp_cexp;
 
-pub fn exp(z: var) Complex(@typeOf(z.re)) {
+pub fn exp(z: var) @typeOf(z) {
     const T = @typeOf(z.re);
 
     return switch (T) {
@@ -16,7 +16,7 @@ pub fn exp(z: var) Complex(@typeOf(z.re)) {
     };
 }
 
-fn exp32(z: *const Complex(f32)) Complex(f32) {
+fn exp32(z: Complex(f32)) Complex(f32) {
     @setFloatMode(this, @import("builtin").FloatMode.Strict);
 
     const exp_overflow = 0x42b17218; // max_exp * ln2 ~= 88.72283955
@@ -63,7 +63,7 @@ fn exp32(z: *const Complex(f32)) Complex(f32) {
     }
 }
 
-fn exp64(z: *const Complex(f64)) Complex(f64) {
+fn exp64(z: Complex(f64)) Complex(f64) {
     const exp_overflow = 0x40862e42; // high bits of max_exp * ln2 ~= 710
     const cexp_overflow = 0x4096b8e4; // (max_exp - min_denorm_exp) * ln2
 
std/math/complex/ldexp.zig
@@ -4,7 +4,7 @@ const math = std.math;
 const cmath = math.complex;
 const Complex = cmath.Complex;
 
-pub fn ldexp_cexp(z: var, expt: i32) Complex(@typeOf(z.re)) {
+pub fn ldexp_cexp(z: var, expt: i32) @typeOf(z) {
     const T = @typeOf(z.re);
 
     return switch (T) {
@@ -20,11 +20,12 @@ fn frexp_exp32(x: f32, expt: *i32) f32 {
 
     const exp_x = math.exp(x - kln2);
     const hx = @bitCast(u32, exp_x);
-    expt.* = i32(hx >> 23) - (0x7f + 127) + k;
+    // TODO zig should allow this cast implicitly because it should know the value is in range
+    expt.* = @intCast(i32, hx >> 23) - (0x7f + 127) + k;
     return @bitCast(f32, (hx & 0x7fffff) | ((0x7f + 127) << 23));
 }
 
-fn ldexp_cexp32(z: *const Complex(f32), expt: i32) Complex(f32) {
+fn ldexp_cexp32(z: Complex(f32), expt: i32) Complex(f32) {
     var ex_expt: i32 = undefined;
     const exp_x = frexp_exp32(z.re, &ex_expt);
     const exptf = expt + ex_expt;
@@ -45,16 +46,16 @@ fn frexp_exp64(x: f64, expt: *i32) f64 {
     const exp_x = math.exp(x - kln2);
 
     const fx = @bitCast(u64, x);
-    const hx = u32(fx >> 32);
+    const hx = @intCast(u32, fx >> 32);
     const lx = @truncate(u32, fx);
 
-    expt.* = i32(hx >> 20) - (0x3ff + 1023) + k;
+    expt.* = @intCast(i32, hx >> 20) - (0x3ff + 1023) + k;
 
     const high_word = (hx & 0xfffff) | ((0x3ff + 1023) << 20);
     return @bitCast(f64, (u64(high_word) << 32) | lx);
 }
 
-fn ldexp_cexp64(z: *const Complex(f64), expt: i32) Complex(f64) {
+fn ldexp_cexp64(z: Complex(f64), expt: i32) Complex(f64) {
     var ex_expt: i32 = undefined;
     const exp_x = frexp_exp64(z.re, &ex_expt);
     const exptf = i64(expt + ex_expt);
std/math/complex/sinh.zig
@@ -6,7 +6,7 @@ const Complex = cmath.Complex;
 
 const ldexp_cexp = @import("ldexp.zig").ldexp_cexp;
 
-pub fn sinh(z: var) Complex(@typeOf(z.re)) {
+pub fn sinh(z: var) @typeOf(z) {
     const T = @typeOf(z.re);
     return switch (T) {
         f32 => sinh32(z),
@@ -15,7 +15,7 @@ pub fn sinh(z: var) Complex(@typeOf(z.re)) {
     };
 }
 
-fn sinh32(z: *const Complex(f32)) Complex(f32) {
+fn sinh32(z: Complex(f32)) Complex(f32) {
     const x = z.re;
     const y = z.im;
 
@@ -78,17 +78,17 @@ fn sinh32(z: *const Complex(f32)) Complex(f32) {
     return Complex(f32).new((x * x) * (y - y), (x + x) * (y - y));
 }
 
-fn sinh64(z: *const Complex(f64)) Complex(f64) {
+fn sinh64(z: Complex(f64)) Complex(f64) {
     const x = z.re;
     const y = z.im;
 
     const fx = @bitCast(u64, x);
-    const hx = u32(fx >> 32);
+    const hx = @intCast(u32, fx >> 32);
     const lx = @truncate(u32, fx);
     const ix = hx & 0x7fffffff;
 
     const fy = @bitCast(u64, y);
-    const hy = u32(fy >> 32);
+    const hy = @intCast(u32, fy >> 32);
     const ly = @truncate(u32, fy);
     const iy = hy & 0x7fffffff;
 
std/math/complex/sqrt.zig
@@ -49,10 +49,16 @@ fn sqrt32(z: Complex(f32)) Complex(f32) {
 
     if (dx >= 0) {
         const t = math.sqrt((dx + math.hypot(f64, dx, dy)) * 0.5);
-        return Complex(f32).new(f32(t), f32(dy / (2.0 * t)));
+        return Complex(f32).new(
+            @floatCast(f32, t),
+            @floatCast(f32, dy / (2.0 * t)),
+        );
     } else {
         const t = math.sqrt((-dx + math.hypot(f64, dx, dy)) * 0.5);
-        return Complex(f32).new(f32(math.fabs(y) / (2.0 * t)), f32(math.copysign(f64, t, y)));
+        return Complex(f32).new(
+            @floatCast(f32, math.fabs(y) / (2.0 * t)),
+            @floatCast(f32, math.copysign(f64, t, y)),
+        );
     }
 }
 
std/math/complex/tanh.zig
@@ -4,7 +4,7 @@ const math = std.math;
 const cmath = math.complex;
 const Complex = cmath.Complex;
 
-pub fn tanh(z: var) Complex(@typeOf(z.re)) {
+pub fn tanh(z: var) @typeOf(z) {
     const T = @typeOf(z.re);
     return switch (T) {
         f32 => tanh32(z),
@@ -13,7 +13,7 @@ pub fn tanh(z: var) Complex(@typeOf(z.re)) {
     };
 }
 
-fn tanh32(z: *const Complex(f32)) Complex(f32) {
+fn tanh32(z: Complex(f32)) Complex(f32) {
     const x = z.re;
     const y = z.im;
 
@@ -51,12 +51,14 @@ fn tanh32(z: *const Complex(f32)) Complex(f32) {
     return Complex(f32).new((beta * rho * s) / den, t / den);
 }
 
-fn tanh64(z: *const Complex(f64)) Complex(f64) {
+fn tanh64(z: Complex(f64)) Complex(f64) {
     const x = z.re;
     const y = z.im;
 
     const fx = @bitCast(u64, x);
-    const hx = u32(fx >> 32);
+    // TODO: zig should allow this conversion implicitly because it can notice that the value necessarily
+    // fits in range.
+    const hx = @intCast(u32, fx >> 32);
     const lx = @truncate(u32, fx);
     const ix = hx & 0x7fffffff;
 
std/math/acos.zig
@@ -95,12 +95,12 @@ fn acos64(x: f64) f64 {
     const pio2_lo: f64 = 6.12323399573676603587e-17;
 
     const ux = @bitCast(u64, x);
-    const hx = u32(ux >> 32);
+    const hx = @intCast(u32, ux >> 32);
     const ix = hx & 0x7FFFFFFF;
 
     // |x| >= 1 or nan
     if (ix >= 0x3FF00000) {
-        const lx = u32(ux & 0xFFFFFFFF);
+        const lx = @intCast(u32, ux & 0xFFFFFFFF);
 
         // acos(1) = 0, acos(-1) = pi
         if ((ix - 0x3FF00000) | lx == 0) {
std/math/asin.zig
@@ -87,12 +87,12 @@ fn asin64(x: f64) f64 {
     const pio2_lo: f64 = 6.12323399573676603587e-17;
 
     const ux = @bitCast(u64, x);
-    const hx = u32(ux >> 32);
+    const hx = @intCast(u32, ux >> 32);
     const ix = hx & 0x7FFFFFFF;
 
     // |x| >= 1 or nan
     if (ix >= 0x3FF00000) {
-        const lx = u32(ux & 0xFFFFFFFF);
+        const lx = @intCast(u32, ux & 0xFFFFFFFF);
 
         // asin(1) = +-pi/2 with inexact
         if ((ix - 0x3FF00000) | lx == 0) {
std/math/atan.zig
@@ -138,7 +138,7 @@ fn atan64(x_: f64) f64 {
 
     var x = x_;
     var ux = @bitCast(u64, x);
-    var ix = u32(ux >> 32);
+    var ix = @intCast(u32, ux >> 32);
     const sign = ix >> 31;
     ix &= 0x7FFFFFFF;
 
@@ -159,7 +159,7 @@ fn atan64(x_: f64) f64 {
         // |x| < 2^(-27)
         if (ix < 0x3E400000) {
             if (ix < 0x00100000) {
-                math.forceEval(f32(x));
+                math.forceEval(@floatCast(f32, x));
             }
             return x;
         }
std/math/atan2.zig
@@ -124,12 +124,12 @@ fn atan2_64(y: f64, x: f64) f64 {
     }
 
     var ux = @bitCast(u64, x);
-    var ix = u32(ux >> 32);
-    var lx = u32(ux & 0xFFFFFFFF);
+    var ix = @intCast(u32, ux >> 32);
+    var lx = @intCast(u32, ux & 0xFFFFFFFF);
 
     var uy = @bitCast(u64, y);
-    var iy = u32(uy >> 32);
-    var ly = u32(uy & 0xFFFFFFFF);
+    var iy = @intCast(u32, uy >> 32);
+    var ly = @intCast(u32, uy & 0xFFFFFFFF);
 
     // x = 1.0
     if ((ix -% 0x3FF00000) | lx == 0) {
std/math/atanh.zig
@@ -62,7 +62,7 @@ fn atanh_64(x: f64) f64 {
         if (e < 0x3FF - 32) {
             // underflow
             if (e == 0) {
-                math.forceEval(f32(y));
+                math.forceEval(@floatCast(f32, y));
             }
         }
         // |x| < 0.5
std/math/cbrt.zig
@@ -54,7 +54,7 @@ fn cbrt32(x: f32) f32 {
     r = t * t * t;
     t = t * (f64(x) + x + r) / (x + r + r);
 
-    return f32(t);
+    return @floatCast(f32, t);
 }
 
 fn cbrt64(x: f64) f64 {
@@ -69,7 +69,7 @@ fn cbrt64(x: f64) f64 {
     const P4: f64 = 0.145996192886612446982;
 
     var u = @bitCast(u64, x);
-    var hx = u32(u >> 32) & 0x7FFFFFFF;
+    var hx = @intCast(u32, u >> 32) & 0x7FFFFFFF;
 
     // cbrt(nan, inf) = itself
     if (hx >= 0x7FF00000) {
@@ -79,7 +79,7 @@ fn cbrt64(x: f64) f64 {
     // cbrt to ~5bits
     if (hx < 0x00100000) {
         u = @bitCast(u64, x * 0x1.0p54);
-        hx = u32(u >> 32) & 0x7FFFFFFF;
+        hx = @intCast(u32, u >> 32) & 0x7FFFFFFF;
 
         // cbrt(0) is itself
         if (hx == 0) {
std/math/ceil.zig
@@ -20,7 +20,7 @@ pub fn ceil(x: var) @typeOf(x) {
 
 fn ceil32(x: f32) f32 {
     var u = @bitCast(u32, x);
-    var e = i32((u >> 23) & 0xFF) - 0x7F;
+    var e = @intCast(i32, (u >> 23) & 0xFF) - 0x7F;
     var m: u32 = undefined;
 
     // TODO: Shouldn't need this explicit check.
@@ -31,7 +31,7 @@ fn ceil32(x: f32) f32 {
     if (e >= 23) {
         return x;
     } else if (e >= 0) {
-        m = u32(0x007FFFFF) >> u5(e);
+        m = u32(0x007FFFFF) >> @intCast(u5, e);
         if (u & m == 0) {
             return x;
         }
std/math/cos.zig
@@ -55,7 +55,7 @@ fn cos32(x_: f32) f32 {
     }
 
     var y = math.floor(x * m4pi);
-    var j = i64(y);
+    var j = @floatToInt(i64, y);
 
     if (j & 1 == 1) {
         j += 1;
@@ -106,7 +106,7 @@ fn cos64(x_: f64) f64 {
     }
 
     var y = math.floor(x * m4pi);
-    var j = i64(y);
+    var j = @floatToInt(i64, y);
 
     if (j & 1 == 1) {
         j += 1;
std/math/cosh.zig
@@ -49,7 +49,7 @@ fn cosh32(x: f32) f32 {
 
 fn cosh64(x: f64) f64 {
     const u = @bitCast(u64, x);
-    const w = u32(u >> 32);
+    const w = @intCast(u32, u >> 32);
     const ax = @bitCast(f64, u & (@maxValue(u64) >> 1));
 
     // TODO: Shouldn't need this explicit check.
std/math/exp.zig
@@ -29,7 +29,7 @@ fn exp32(x_: f32) f32 {
 
     var x = x_;
     var hx = @bitCast(u32, x);
-    const sign = i32(hx >> 31);
+    const sign = @intCast(i32, hx >> 31);
     hx &= 0x7FFFFFFF;
 
     if (math.isNan(x)) {
@@ -63,12 +63,12 @@ fn exp32(x_: f32) f32 {
     if (hx > 0x3EB17218) {
         // |x| > 1.5 * ln2
         if (hx > 0x3F851592) {
-            k = i32(invln2 * x + half[usize(sign)]);
+            k = @floatToInt(i32, invln2 * x + half[@intCast(usize, sign)]);
         } else {
             k = 1 - sign - sign;
         }
 
-        const fk = f32(k);
+        const fk = @intToFloat(f32, k);
         hi = x - fk * ln2hi;
         lo = fk * ln2lo;
         x = hi - lo;
@@ -110,7 +110,7 @@ fn exp64(x_: f64) f64 {
     var x = x_;
     var ux = @bitCast(u64, x);
     var hx = ux >> 32;
-    const sign = i32(hx >> 31);
+    const sign = @intCast(i32, hx >> 31);
     hx &= 0x7FFFFFFF;
 
     if (math.isNan(x)) {
@@ -148,12 +148,12 @@ fn exp64(x_: f64) f64 {
     if (hx > 0x3EB17218) {
         // |x| >= 1.5 * ln2
         if (hx > 0x3FF0A2B2) {
-            k = i32(invln2 * x + half[usize(sign)]);
+            k = @floatToInt(i32, invln2 * x + half[@intCast(usize, sign)]);
         } else {
             k = 1 - sign - sign;
         }
 
-        const dk = f64(k);
+        const dk = @intToFloat(f64, k);
         hi = x - dk * ln2hi;
         lo = dk * ln2lo;
         x = hi - lo;
std/math/exp2.zig
@@ -38,8 +38,8 @@ const exp2ft = []const f64{
 fn exp2_32(x: f32) f32 {
     @setFloatMode(this, @import("builtin").FloatMode.Strict);
 
-    const tblsiz = u32(exp2ft.len);
-    const redux: f32 = 0x1.8p23 / f32(tblsiz);
+    const tblsiz = @intCast(u32, exp2ft.len);
+    const redux: f32 = 0x1.8p23 / @intToFloat(f32, tblsiz);
     const P1: f32 = 0x1.62e430p-1;
     const P2: f32 = 0x1.ebfbe0p-3;
     const P3: f32 = 0x1.c6b348p-5;
@@ -89,7 +89,7 @@ fn exp2_32(x: f32) f32 {
     var r: f64 = exp2ft[i0];
     const t: f64 = r * z;
     r = r + t * (P1 + z * P2) + t * (z * z) * (P3 + z * P4);
-    return f32(r * uk);
+    return @floatCast(f32, r * uk);
 }
 
 const exp2dt = []f64{
@@ -355,8 +355,8 @@ const exp2dt = []f64{
 fn exp2_64(x: f64) f64 {
     @setFloatMode(this, @import("builtin").FloatMode.Strict);
 
-    const tblsiz = u32(exp2dt.len / 2);
-    const redux: f64 = 0x1.8p52 / f64(tblsiz);
+    const tblsiz = @intCast(u32, exp2dt.len / 2);
+    const redux: f64 = 0x1.8p52 / @intToFloat(f64, tblsiz);
     const P1: f64 = 0x1.62e42fefa39efp-1;
     const P2: f64 = 0x1.ebfbdff82c575p-3;
     const P3: f64 = 0x1.c6b08d704a0a6p-5;
@@ -364,7 +364,7 @@ fn exp2_64(x: f64) f64 {
     const P5: f64 = 0x1.5d88003875c74p-10;
 
     const ux = @bitCast(u64, x);
-    const ix = u32(ux >> 32) & 0x7FFFFFFF;
+    const ix = @intCast(u32, ux >> 32) & 0x7FFFFFFF;
 
     // TODO: This should be handled beneath.
     if (math.isNan(x)) {
@@ -386,7 +386,7 @@ fn exp2_64(x: f64) f64 {
         if (ux >> 63 != 0) {
             // underflow
             if (x <= -1075 or x - 0x1.0p52 + 0x1.0p52 != x) {
-                math.forceEval(f32(-0x1.0p-149 / x));
+                math.forceEval(@floatCast(f32, -0x1.0p-149 / x));
             }
             if (x <= -1075) {
                 return 0;
std/math/expm1.zig
@@ -78,8 +78,8 @@ fn expm1_32(x_: f32) f32 {
                 kf += 0.5;
             }
 
-            k = i32(kf);
-            const t = f32(k);
+            k = @floatToInt(i32, kf);
+            const t = @intToFloat(f32, k);
             hi = x - t * ln2_hi;
             lo = t * ln2_lo;
         }
@@ -123,7 +123,7 @@ fn expm1_32(x_: f32) f32 {
         }
     }
 
-    const twopk = @bitCast(f32, u32((0x7F +% k) << 23));
+    const twopk = @bitCast(f32, @intCast(u32, (0x7F +% k) << 23));
 
     if (k < 0 or k > 56) {
         var y = x - e + 1.0;
@@ -136,7 +136,7 @@ fn expm1_32(x_: f32) f32 {
         return y - 1.0;
     }
 
-    const uf = @bitCast(f32, u32(0x7F -% k) << 23);
+    const uf = @bitCast(f32, @intCast(u32, 0x7F -% k) << 23);
     if (k < 23) {
         return (x - e + (1 - uf)) * twopk;
     } else {
@@ -158,7 +158,7 @@ fn expm1_64(x_: f64) f64 {
 
     var x = x_;
     const ux = @bitCast(u64, x);
-    const hx = u32(ux >> 32) & 0x7FFFFFFF;
+    const hx = @intCast(u32, ux >> 32) & 0x7FFFFFFF;
     const sign = ux >> 63;
 
     if (math.isNegativeInf(x)) {
@@ -207,8 +207,8 @@ fn expm1_64(x_: f64) f64 {
                 kf += 0.5;
             }
 
-            k = i32(kf);
-            const t = f64(k);
+            k = @floatToInt(i32, kf);
+            const t = @intToFloat(f64, k);
             hi = x - t * ln2_hi;
             lo = t * ln2_lo;
         }
@@ -219,7 +219,7 @@ fn expm1_64(x_: f64) f64 {
     // |x| < 2^(-54)
     else if (hx < 0x3C900000) {
         if (hx < 0x00100000) {
-            math.forceEval(f32(x));
+            math.forceEval(@floatCast(f32, x));
         }
         return x;
     } else {
@@ -252,7 +252,7 @@ fn expm1_64(x_: f64) f64 {
         }
     }
 
-    const twopk = @bitCast(f64, u64(0x3FF +% k) << 52);
+    const twopk = @bitCast(f64, @intCast(u64, 0x3FF +% k) << 52);
 
     if (k < 0 or k > 56) {
         var y = x - e + 1.0;
@@ -265,7 +265,7 @@ fn expm1_64(x_: f64) f64 {
         return y - 1.0;
     }
 
-    const uf = @bitCast(f64, u64(0x3FF -% k) << 52);
+    const uf = @bitCast(f64, @intCast(u64, 0x3FF -% k) << 52);
     if (k < 20) {
         return (x - e + (1 - uf)) * twopk;
     } else {
std/math/floor.zig
@@ -20,7 +20,7 @@ pub fn floor(x: var) @typeOf(x) {
 
 fn floor32(x: f32) f32 {
     var u = @bitCast(u32, x);
-    const e = i32((u >> 23) & 0xFF) - 0x7F;
+    const e = @intCast(i32, (u >> 23) & 0xFF) - 0x7F;
     var m: u32 = undefined;
 
     // TODO: Shouldn't need this explicit check.
@@ -33,7 +33,7 @@ fn floor32(x: f32) f32 {
     }
 
     if (e >= 0) {
-        m = u32(0x007FFFFF) >> u5(e);
+        m = u32(0x007FFFFF) >> @intCast(u5, e);
         if (u & m == 0) {
             return x;
         }
std/math/fma.zig
@@ -17,10 +17,10 @@ fn fma32(x: f32, y: f32, z: f32) f32 {
     const e = (u >> 52) & 0x7FF;
 
     if ((u & 0x1FFFFFFF) != 0x10000000 or e == 0x7FF or xy_z - xy == z) {
-        return f32(xy_z);
+        return @floatCast(f32, xy_z);
     } else {
         // TODO: Handle inexact case with double-rounding
-        return f32(xy_z);
+        return @floatCast(f32, xy_z);
     }
 }
 
@@ -124,7 +124,7 @@ fn add_and_denorm(a: f64, b: f64, scale: i32) f64 {
     var sum = dd_add(a, b);
     if (sum.lo != 0) {
         var uhii = @bitCast(u64, sum.hi);
-        const bits_lost = -i32((uhii >> 52) & 0x7FF) - scale + 1;
+        const bits_lost = -@intCast(i32, (uhii >> 52) & 0x7FF) - scale + 1;
         if ((bits_lost != 1) == (uhii & 1 != 0)) {
             const uloi = @bitCast(u64, sum.lo);
             uhii += 1 - (((uhii ^ uloi) >> 62) & 2);
std/math/frexp.zig
@@ -30,7 +30,7 @@ fn frexp32(x: f32) frexp32_result {
     var result: frexp32_result = undefined;
 
     var y = @bitCast(u32, x);
-    const e = i32(y >> 23) & 0xFF;
+    const e = @intCast(i32, y >> 23) & 0xFF;
 
     if (e == 0) {
         if (x != 0) {
@@ -67,7 +67,7 @@ fn frexp64(x: f64) frexp64_result {
     var result: frexp64_result = undefined;
 
     var y = @bitCast(u64, x);
-    const e = i32(y >> 52) & 0x7FF;
+    const e = @intCast(i32, y >> 52) & 0x7FF;
 
     if (e == 0) {
         if (x != 0) {
std/math/hypot.zig
@@ -49,7 +49,7 @@ fn hypot32(x: f32, y: f32) f32 {
         yy *= 0x1.0p-90;
     }
 
-    return z * math.sqrt(f32(f64(x) * x + f64(y) * y));
+    return z * math.sqrt(@floatCast(f32, f64(x) * x + f64(y) * y));
 }
 
 fn sq(hi: *f64, lo: *f64, x: f64) void {
std/math/ilogb.zig
@@ -23,7 +23,7 @@ const fp_ilogb0 = fp_ilogbnan;
 
 fn ilogb32(x: f32) i32 {
     var u = @bitCast(u32, x);
-    var e = i32((u >> 23) & 0xFF);
+    var e = @intCast(i32, (u >> 23) & 0xFF);
 
     // TODO: We should be able to merge this with the lower check.
     if (math.isNan(x)) {
@@ -59,7 +59,7 @@ fn ilogb32(x: f32) i32 {
 
 fn ilogb64(x: f64) i32 {
     var u = @bitCast(u64, x);
-    var e = i32((u >> 52) & 0x7FF);
+    var e = @intCast(i32, (u >> 52) & 0x7FF);
 
     if (math.isNan(x)) {
         return @maxValue(i32);
std/math/index.zig
@@ -227,7 +227,7 @@ pub fn shlExact(comptime T: type, a: T, shift_amt: Log2Int(T)) !T {
 /// A negative shift amount results in a right shift.
 pub fn shl(comptime T: type, a: T, shift_amt: var) T {
     const abs_shift_amt = absCast(shift_amt);
-    const casted_shift_amt = if (abs_shift_amt >= T.bit_count) return 0 else Log2Int(T)(abs_shift_amt);
+    const casted_shift_amt = if (abs_shift_amt >= T.bit_count) return 0 else @intCast(Log2Int(T), abs_shift_amt);
 
     if (@typeOf(shift_amt).is_signed) {
         if (shift_amt >= 0) {
@@ -251,7 +251,7 @@ test "math.shl" {
 /// A negative shift amount results in a lefft shift.
 pub fn shr(comptime T: type, a: T, shift_amt: var) T {
     const abs_shift_amt = absCast(shift_amt);
-    const casted_shift_amt = if (abs_shift_amt >= T.bit_count) return 0 else Log2Int(T)(abs_shift_amt);
+    const casted_shift_amt = if (abs_shift_amt >= T.bit_count) return 0 else @intCast(Log2Int(T), abs_shift_amt);
 
     if (@typeOf(shift_amt).is_signed) {
         if (shift_amt >= 0) {
@@ -473,9 +473,9 @@ fn testRem() void {
 /// Result is an unsigned integer.
 pub fn absCast(x: var) @IntType(false, @typeOf(x).bit_count) {
     const uint = @IntType(false, @typeOf(x).bit_count);
-    if (x >= 0) return uint(x);
+    if (x >= 0) return @intCast(uint, x);
 
-    return uint(-(x + 1)) + 1;
+    return @intCast(uint, -(x + 1)) + 1;
 }
 
 test "math.absCast" {
@@ -499,7 +499,7 @@ pub fn negateCast(x: var) !@IntType(true, @typeOf(x).bit_count) {
 
     if (x == -@minValue(int)) return @minValue(int);
 
-    return -int(x);
+    return -@intCast(int, x);
 }
 
 test "math.negateCast" {
@@ -522,7 +522,7 @@ pub fn cast(comptime T: type, x: var) (error{Overflow}!T) {
     } else if (@minValue(@typeOf(x)) < @minValue(T) and x < @minValue(T)) {
         return error.Overflow;
     } else {
-        return T(x);
+        return @intCast(T, x);
     }
 }
 
@@ -565,7 +565,7 @@ test "math.floorPowerOfTwo" {
 
 pub fn log2_int(comptime T: type, x: T) Log2Int(T) {
     assert(x != 0);
-    return Log2Int(T)(T.bit_count - 1 - @clz(x));
+    return @intCast(Log2Int(T), T.bit_count - 1 - @clz(x));
 }
 
 pub fn log2_int_ceil(comptime T: type, x: T) Log2Int(T) {
@@ -597,3 +597,14 @@ fn testFloorPowerOfTwo() void {
     assert(floorPowerOfTwo(u4, 8) == 8);
     assert(floorPowerOfTwo(u4, 9) == 8);
 }
+
+pub fn lossyCast(comptime T: type, value: var) T {
+    switch (@typeInfo(@typeOf(value))) {
+        builtin.TypeId.Int => return @intToFloat(T, value),
+        builtin.TypeId.Float => return @floatCast(T, value),
+        builtin.TypeId.ComptimeInt => return T(value),
+        builtin.TypeId.ComptimeFloat => return T(value),
+        else => @compileError("bad type"),
+    }
+}
+
std/math/ln.zig
@@ -71,7 +71,7 @@ pub fn ln_32(x_: f32) f32 {
 
     // x into [sqrt(2) / 2, sqrt(2)]
     ix += 0x3F800000 - 0x3F3504F3;
-    k += i32(ix >> 23) - 0x7F;
+    k += @intCast(i32, ix >> 23) - 0x7F;
     ix = (ix & 0x007FFFFF) + 0x3F3504F3;
     x = @bitCast(f32, ix);
 
@@ -83,7 +83,7 @@ pub fn ln_32(x_: f32) f32 {
     const t2 = z * (Lg1 + w * Lg3);
     const R = t2 + t1;
     const hfsq = 0.5 * f * f;
-    const dk = f32(k);
+    const dk = @intToFloat(f32, k);
 
     return s * (hfsq + R) + dk * ln2_lo - hfsq + f + dk * ln2_hi;
 }
@@ -103,7 +103,7 @@ pub fn ln_64(x_: f64) f64 {
 
     var x = x_;
     var ix = @bitCast(u64, x);
-    var hx = u32(ix >> 32);
+    var hx = @intCast(u32, ix >> 32);
     var k: i32 = 0;
 
     if (hx < 0x00100000 or hx >> 31 != 0) {
@@ -119,7 +119,7 @@ pub fn ln_64(x_: f64) f64 {
         // subnormal, scale x
         k -= 54;
         x *= 0x1.0p54;
-        hx = u32(@bitCast(u64, ix) >> 32);
+        hx = @intCast(u32, @bitCast(u64, ix) >> 32);
     } else if (hx >= 0x7FF00000) {
         return x;
     } else if (hx == 0x3FF00000 and ix << 32 == 0) {
@@ -128,7 +128,7 @@ pub fn ln_64(x_: f64) f64 {
 
     // x into [sqrt(2) / 2, sqrt(2)]
     hx += 0x3FF00000 - 0x3FE6A09E;
-    k += i32(hx >> 20) - 0x3FF;
+    k += @intCast(i32, hx >> 20) - 0x3FF;
     hx = (hx & 0x000FFFFF) + 0x3FE6A09E;
     ix = (u64(hx) << 32) | (ix & 0xFFFFFFFF);
     x = @bitCast(f64, ix);
@@ -141,7 +141,7 @@ pub fn ln_64(x_: f64) f64 {
     const t1 = w * (Lg2 + w * (Lg4 + w * Lg6));
     const t2 = z * (Lg1 + w * (Lg3 + w * (Lg5 + w * Lg7)));
     const R = t2 + t1;
-    const dk = f64(k);
+    const dk = @intToFloat(f64, k);
 
     return s * (hfsq + R) + dk * ln2_lo - hfsq + f + dk * ln2_hi;
 }
std/math/log.zig
@@ -13,22 +13,23 @@ pub fn log(comptime T: type, base: T, x: T) T {
         return math.ln(x);
     }
 
+    const float_base = math.lossyCast(f64, base);
     switch (@typeId(T)) {
         TypeId.ComptimeFloat => {
-            return @typeOf(1.0)(math.ln(f64(x)) / math.ln(f64(base)));
+            return @typeOf(1.0)(math.ln(f64(x)) / math.ln(float_base));
         },
         TypeId.ComptimeInt => {
-            return @typeOf(1)(math.floor(math.ln(f64(x)) / math.ln(f64(base))));
+            return @typeOf(1)(math.floor(math.ln(f64(x)) / math.ln(float_base)));
         },
         builtin.TypeId.Int => {
             // TODO implement integer log without using float math
-            return T(math.floor(math.ln(f64(x)) / math.ln(f64(base))));
+            return @floatToInt(T, math.floor(math.ln(@intToFloat(f64, x)) / math.ln(float_base)));
         },
 
         builtin.TypeId.Float => {
             switch (T) {
-                f32 => return f32(math.ln(f64(x)) / math.ln(f64(base))),
-                f64 => return math.ln(x) / math.ln(f64(base)),
+                f32 => return @floatCast(f32, math.ln(f64(x)) / math.ln(float_base)),
+                f64 => return math.ln(x) / math.ln(float_base),
                 else => @compileError("log not implemented for " ++ @typeName(T)),
             }
         },
std/math/log10.zig
@@ -28,7 +28,7 @@ pub fn log10(x: var) @typeOf(x) {
             return @typeOf(1)(math.floor(log10_64(f64(x))));
         },
         TypeId.Int => {
-            return T(math.floor(log10_64(f64(x))));
+            return @floatToInt(T, math.floor(log10_64(@intToFloat(f64, x))));
         },
         else => @compileError("log10 not implemented for " ++ @typeName(T)),
     }
@@ -71,7 +71,7 @@ pub fn log10_32(x_: f32) f32 {
 
     // x into [sqrt(2) / 2, sqrt(2)]
     ix += 0x3F800000 - 0x3F3504F3;
-    k += i32(ix >> 23) - 0x7F;
+    k += @intCast(i32, ix >> 23) - 0x7F;
     ix = (ix & 0x007FFFFF) + 0x3F3504F3;
     x = @bitCast(f32, ix);
 
@@ -89,7 +89,7 @@ pub fn log10_32(x_: f32) f32 {
     u &= 0xFFFFF000;
     hi = @bitCast(f32, u);
     const lo = f - hi - hfsq + s * (hfsq + R);
-    const dk = f32(k);
+    const dk = @intToFloat(f32, k);
 
     return dk * log10_2lo + (lo + hi) * ivln10lo + lo * ivln10hi + hi * ivln10hi + dk * log10_2hi;
 }
@@ -109,7 +109,7 @@ pub fn log10_64(x_: f64) f64 {
 
     var x = x_;
     var ix = @bitCast(u64, x);
-    var hx = u32(ix >> 32);
+    var hx = @intCast(u32, ix >> 32);
     var k: i32 = 0;
 
     if (hx < 0x00100000 or hx >> 31 != 0) {
@@ -125,7 +125,7 @@ pub fn log10_64(x_: f64) f64 {
         // subnormal, scale x
         k -= 54;
         x *= 0x1.0p54;
-        hx = u32(@bitCast(u64, x) >> 32);
+        hx = @intCast(u32, @bitCast(u64, x) >> 32);
     } else if (hx >= 0x7FF00000) {
         return x;
     } else if (hx == 0x3FF00000 and ix << 32 == 0) {
@@ -134,7 +134,7 @@ pub fn log10_64(x_: f64) f64 {
 
     // x into [sqrt(2) / 2, sqrt(2)]
     hx += 0x3FF00000 - 0x3FE6A09E;
-    k += i32(hx >> 20) - 0x3FF;
+    k += @intCast(i32, hx >> 20) - 0x3FF;
     hx = (hx & 0x000FFFFF) + 0x3FE6A09E;
     ix = (u64(hx) << 32) | (ix & 0xFFFFFFFF);
     x = @bitCast(f64, ix);
@@ -157,7 +157,7 @@ pub fn log10_64(x_: f64) f64 {
 
     // val_hi + val_lo ~ log10(1 + f) + k * log10(2)
     var val_hi = hi * ivln10hi;
-    const dk = f64(k);
+    const dk = @intToFloat(f64, k);
     const y = dk * log10_2hi;
     var val_lo = dk * log10_2lo + (lo + hi) * ivln10lo + lo * ivln10hi;
 
std/math/log1p.zig
@@ -68,7 +68,7 @@ fn log1p_32(x: f32) f32 {
         const uf = 1 + x;
         var iu = @bitCast(u32, uf);
         iu += 0x3F800000 - 0x3F3504F3;
-        k = i32(iu >> 23) - 0x7F;
+        k = @intCast(i32, iu >> 23) - 0x7F;
 
         // correction to avoid underflow in c / u
         if (k < 25) {
@@ -90,7 +90,7 @@ fn log1p_32(x: f32) f32 {
     const t2 = z * (Lg1 + w * Lg3);
     const R = t2 + t1;
     const hfsq = 0.5 * f * f;
-    const dk = f32(k);
+    const dk = @intToFloat(f32, k);
 
     return s * (hfsq + R) + (dk * ln2_lo + c) - hfsq + f + dk * ln2_hi;
 }
@@ -107,7 +107,7 @@ fn log1p_64(x: f64) f64 {
     const Lg7: f64 = 1.479819860511658591e-01;
 
     var ix = @bitCast(u64, x);
-    var hx = u32(ix >> 32);
+    var hx = @intCast(u32, ix >> 32);
     var k: i32 = 1;
     var c: f64 = undefined;
     var f: f64 = undefined;
@@ -145,9 +145,9 @@ fn log1p_64(x: f64) f64 {
     if (k != 0) {
         const uf = 1 + x;
         const hu = @bitCast(u64, uf);
-        var iu = u32(hu >> 32);
+        var iu = @intCast(u32, hu >> 32);
         iu += 0x3FF00000 - 0x3FE6A09E;
-        k = i32(iu >> 20) - 0x3FF;
+        k = @intCast(i32, iu >> 20) - 0x3FF;
 
         // correction to avoid underflow in c / u
         if (k < 54) {
@@ -170,7 +170,7 @@ fn log1p_64(x: f64) f64 {
     const t1 = w * (Lg2 + w * (Lg4 + w * Lg6));
     const t2 = z * (Lg1 + w * (Lg3 + w * (Lg5 + w * Lg7)));
     const R = t2 + t1;
-    const dk = f64(k);
+    const dk = @intToFloat(f64, k);
 
     return s * (hfsq + R) + (dk * ln2_lo + c) - hfsq + f + dk * ln2_hi;
 }
std/math/log2.zig
@@ -75,7 +75,7 @@ pub fn log2_32(x_: f32) f32 {
 
     // x into [sqrt(2) / 2, sqrt(2)]
     ix += 0x3F800000 - 0x3F3504F3;
-    k += i32(ix >> 23) - 0x7F;
+    k += @intCast(i32, ix >> 23) - 0x7F;
     ix = (ix & 0x007FFFFF) + 0x3F3504F3;
     x = @bitCast(f32, ix);
 
@@ -93,7 +93,7 @@ pub fn log2_32(x_: f32) f32 {
     u &= 0xFFFFF000;
     hi = @bitCast(f32, u);
     const lo = f - hi - hfsq + s * (hfsq + R);
-    return (lo + hi) * ivln2lo + lo * ivln2hi + hi * ivln2hi + f32(k);
+    return (lo + hi) * ivln2lo + lo * ivln2hi + hi * ivln2hi + @intToFloat(f32, k);
 }
 
 pub fn log2_64(x_: f64) f64 {
@@ -109,7 +109,7 @@ pub fn log2_64(x_: f64) f64 {
 
     var x = x_;
     var ix = @bitCast(u64, x);
-    var hx = u32(ix >> 32);
+    var hx = @intCast(u32, ix >> 32);
     var k: i32 = 0;
 
     if (hx < 0x00100000 or hx >> 31 != 0) {
@@ -125,7 +125,7 @@ pub fn log2_64(x_: f64) f64 {
         // subnormal, scale x
         k -= 54;
         x *= 0x1.0p54;
-        hx = u32(@bitCast(u64, x) >> 32);
+        hx = @intCast(u32, @bitCast(u64, x) >> 32);
     } else if (hx >= 0x7FF00000) {
         return x;
     } else if (hx == 0x3FF00000 and ix << 32 == 0) {
@@ -134,7 +134,7 @@ pub fn log2_64(x_: f64) f64 {
 
     // x into [sqrt(2) / 2, sqrt(2)]
     hx += 0x3FF00000 - 0x3FE6A09E;
-    k += i32(hx >> 20) - 0x3FF;
+    k += @intCast(i32, hx >> 20) - 0x3FF;
     hx = (hx & 0x000FFFFF) + 0x3FE6A09E;
     ix = (u64(hx) << 32) | (ix & 0xFFFFFFFF);
     x = @bitCast(f64, ix);
@@ -159,7 +159,7 @@ pub fn log2_64(x_: f64) f64 {
     var val_lo = (lo + hi) * ivln2lo + lo * ivln2hi;
 
     // spadd(val_hi, val_lo, y)
-    const y = f64(k);
+    const y = @intToFloat(f64, k);
     const ww = y + val_hi;
     val_lo += (y - ww) + val_hi;
     val_hi = ww;
std/math/modf.zig
@@ -29,7 +29,7 @@ fn modf32(x: f32) modf32_result {
     var result: modf32_result = undefined;
 
     const u = @bitCast(u32, x);
-    const e = i32((u >> 23) & 0xFF) - 0x7F;
+    const e = @intCast(i32, (u >> 23) & 0xFF) - 0x7F;
     const us = u & 0x80000000;
 
     // TODO: Shouldn't need this.
@@ -57,7 +57,7 @@ fn modf32(x: f32) modf32_result {
         return result;
     }
 
-    const mask = u32(0x007FFFFF) >> u5(e);
+    const mask = u32(0x007FFFFF) >> @intCast(u5, e);
     if (u & mask == 0) {
         result.ipart = x;
         result.fpart = @bitCast(f32, us);
@@ -74,7 +74,7 @@ fn modf64(x: f64) modf64_result {
     var result: modf64_result = undefined;
 
     const u = @bitCast(u64, x);
-    const e = i32((u >> 52) & 0x7FF) - 0x3FF;
+    const e = @intCast(i32, (u >> 52) & 0x7FF) - 0x3FF;
     const us = u & (1 << 63);
 
     if (math.isInf(x)) {
@@ -101,7 +101,7 @@ fn modf64(x: f64) modf64_result {
         return result;
     }
 
-    const mask = u64(@maxValue(u64) >> 12) >> u6(e);
+    const mask = u64(@maxValue(u64) >> 12) >> @intCast(u6, e);
     if (u & mask == 0) {
         result.ipart = x;
         result.fpart = @bitCast(f64, us);
std/math/pow.zig
@@ -146,7 +146,7 @@ pub fn pow(comptime T: type, x: T, y: T) T {
     var xe = r2.exponent;
     var x1 = r2.significand;
 
-    var i = i32(yi);
+    var i = @floatToInt(i32, yi);
     while (i != 0) : (i >>= 1) {
         if (i & 1 == 1) {
             a1 *= x1;
@@ -171,7 +171,7 @@ pub fn pow(comptime T: type, x: T, y: T) T {
 
 fn isOddInteger(x: f64) bool {
     const r = math.modf(x);
-    return r.fpart == 0.0 and i64(r.ipart) & 1 == 1;
+    return r.fpart == 0.0 and @floatToInt(i64, r.ipart) & 1 == 1;
 }
 
 test "math.pow" {
std/math/scalbn.zig
@@ -37,7 +37,7 @@ fn scalbn32(x: f32, n_: i32) f32 {
         }
     }
 
-    const u = u32(n +% 0x7F) << 23;
+    const u = @intCast(u32, n +% 0x7F) << 23;
     return y * @bitCast(f32, u);
 }
 
@@ -67,7 +67,7 @@ fn scalbn64(x: f64, n_: i32) f64 {
         }
     }
 
-    const u = u64(n +% 0x3FF) << 52;
+    const u = @intCast(u64, n +% 0x3FF) << 52;
     return y * @bitCast(f64, u);
 }
 
std/math/sin.zig
@@ -60,7 +60,7 @@ fn sin32(x_: f32) f32 {
     }
 
     var y = math.floor(x * m4pi);
-    var j = i64(y);
+    var j = @floatToInt(i64, y);
 
     if (j & 1 == 1) {
         j += 1;
@@ -112,7 +112,7 @@ fn sin64(x_: f64) f64 {
     }
 
     var y = math.floor(x * m4pi);
-    var j = i64(y);
+    var j = @floatToInt(i64, y);
 
     if (j & 1 == 1) {
         j += 1;
std/math/sinh.zig
@@ -57,7 +57,7 @@ fn sinh64(x: f64) f64 {
     @setFloatMode(this, @import("builtin").FloatMode.Strict);
 
     const u = @bitCast(u64, x);
-    const w = u32(u >> 32);
+    const w = @intCast(u32, u >> 32);
     const ax = @bitCast(f64, u & (@maxValue(u64) >> 1));
 
     if (x == 0.0 or math.isNan(x)) {
std/math/sqrt.zig
@@ -99,7 +99,7 @@ fn sqrt_int(comptime T: type, value: T) @IntType(false, T.bit_count / 2) {
     }
 
     const ResultType = @IntType(false, T.bit_count / 2);
-    return ResultType(res);
+    return @intCast(ResultType, res);
 }
 
 test "math.sqrt_int" {
std/math/tan.zig
@@ -53,7 +53,7 @@ fn tan32(x_: f32) f32 {
     }
 
     var y = math.floor(x * m4pi);
-    var j = i64(y);
+    var j = @floatToInt(i64, y);
 
     if (j & 1 == 1) {
         j += 1;
@@ -102,7 +102,7 @@ fn tan64(x_: f64) f64 {
     }
 
     var y = math.floor(x * m4pi);
-    var j = i64(y);
+    var j = @floatToInt(i64, y);
 
     if (j & 1 == 1) {
         j += 1;
std/math/tanh.zig
@@ -68,7 +68,7 @@ fn tanh32(x: f32) f32 {
 
 fn tanh64(x: f64) f64 {
     const u = @bitCast(u64, x);
-    const w = u32(u >> 32);
+    const w = @intCast(u32, u >> 32);
     const ax = @bitCast(f64, u & (@maxValue(u64) >> 1));
 
     var t: f64 = undefined;
@@ -100,7 +100,7 @@ fn tanh64(x: f64) f64 {
     }
     // |x| is subnormal
     else {
-        math.forceEval(f32(x));
+        math.forceEval(@floatCast(f32, x));
         t = x;
     }
 
std/math/trunc.zig
@@ -19,7 +19,7 @@ pub fn trunc(x: var) @typeOf(x) {
 
 fn trunc32(x: f32) f32 {
     const u = @bitCast(u32, x);
-    var e = i32(((u >> 23) & 0xFF)) - 0x7F + 9;
+    var e = @intCast(i32, ((u >> 23) & 0xFF)) - 0x7F + 9;
     var m: u32 = undefined;
 
     if (e >= 23 + 9) {
@@ -29,7 +29,7 @@ fn trunc32(x: f32) f32 {
         e = 1;
     }
 
-    m = u32(@maxValue(u32)) >> u5(e);
+    m = u32(@maxValue(u32)) >> @intCast(u5, e);
     if (u & m == 0) {
         return x;
     } else {
@@ -40,7 +40,7 @@ fn trunc32(x: f32) f32 {
 
 fn trunc64(x: f64) f64 {
     const u = @bitCast(u64, x);
-    var e = i32(((u >> 52) & 0x7FF)) - 0x3FF + 12;
+    var e = @intCast(i32, ((u >> 52) & 0x7FF)) - 0x3FF + 12;
     var m: u64 = undefined;
 
     if (e >= 52 + 12) {
@@ -50,7 +50,7 @@ fn trunc64(x: f64) f64 {
         e = 1;
     }
 
-    m = u64(@maxValue(u64)) >> u6(e);
+    m = u64(@maxValue(u64)) >> @intCast(u6, e);
     if (u & m == 0) {
         return x;
     } else {
std/os/linux/index.zig
@@ -642,7 +642,7 @@ pub fn WIFEXITED(s: i32) bool {
     return WTERMSIG(s) == 0;
 }
 pub fn WIFSTOPPED(s: i32) bool {
-    return (u16)(((unsigned(s) & 0xffff) *% 0x10001) >> 8) > 0x7f00;
+    return @intCast(u16, ((unsigned(s) & 0xffff) *% 0x10001) >> 8) > 0x7f00;
 }
 pub fn WIFSIGNALED(s: i32) bool {
     return (unsigned(s) & 0xffff) -% 1 < 0xff;
@@ -658,11 +658,11 @@ pub const winsize = extern struct {
 /// Get the errno from a syscall return value, or 0 for no error.
 pub fn getErrno(r: usize) usize {
     const signed_r = @bitCast(isize, r);
-    return if (signed_r > -4096 and signed_r < 0) usize(-signed_r) else 0;
+    return if (signed_r > -4096 and signed_r < 0) @intCast(usize, -signed_r) else 0;
 }
 
 pub fn dup2(old: i32, new: i32) usize {
-    return syscall2(SYS_dup2, usize(old), usize(new));
+    return syscall2(SYS_dup2, @intCast(usize, old), @intCast(usize, new));
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -693,12 +693,12 @@ pub fn getcwd(buf: [*]u8, size: usize) usize {
 }
 
 pub fn getdents(fd: i32, dirp: [*]u8, count: usize) usize {
-    return syscall3(SYS_getdents, usize(fd), @ptrToInt(dirp), count);
+    return syscall3(SYS_getdents, @intCast(usize, fd), @ptrToInt(dirp), count);
 }
 
 pub fn isatty(fd: i32) bool {
     var wsz: winsize = undefined;
-    return syscall3(SYS_ioctl, usize(fd), TIOCGWINSZ, @ptrToInt(&wsz)) == 0;
+    return syscall3(SYS_ioctl, @intCast(usize, fd), TIOCGWINSZ, @ptrToInt(&wsz)) == 0;
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -727,7 +727,7 @@ pub fn umount2(special: [*]const u8, flags: u32) usize {
 }
 
 pub fn mmap(address: ?[*]u8, length: usize, prot: usize, flags: u32, fd: i32, offset: isize) usize {
-    return syscall6(SYS_mmap, @ptrToInt(address), length, prot, flags, usize(fd), @bitCast(usize, offset));
+    return syscall6(SYS_mmap, @ptrToInt(address), length, prot, flags, @intCast(usize, fd), @bitCast(usize, offset));
 }
 
 pub fn munmap(address: usize, length: usize) usize {
@@ -735,7 +735,7 @@ pub fn munmap(address: usize, length: usize) usize {
 }
 
 pub fn read(fd: i32, buf: [*]u8, count: usize) usize {
-    return syscall3(SYS_read, usize(fd), @ptrToInt(buf), count);
+    return syscall3(SYS_read, @intCast(usize, fd), @ptrToInt(buf), count);
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -749,7 +749,7 @@ pub fn symlink(existing: [*]const u8, new: [*]const u8) usize {
 }
 
 pub fn pread(fd: i32, buf: [*]u8, count: usize, offset: usize) usize {
-    return syscall4(SYS_pread, usize(fd), @ptrToInt(buf), count, offset);
+    return syscall4(SYS_pread, @intCast(usize, fd), @ptrToInt(buf), count, offset);
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -766,11 +766,11 @@ pub fn pipe2(fd: *[2]i32, flags: usize) usize {
 }
 
 pub fn write(fd: i32, buf: [*]const u8, count: usize) usize {
-    return syscall3(SYS_write, usize(fd), @ptrToInt(buf), count);
+    return syscall3(SYS_write, @intCast(usize, fd), @ptrToInt(buf), count);
 }
 
 pub fn pwrite(fd: i32, buf: [*]const u8, count: usize, offset: usize) usize {
-    return syscall4(SYS_pwrite, usize(fd), @ptrToInt(buf), count, offset);
+    return syscall4(SYS_pwrite, @intCast(usize, fd), @ptrToInt(buf), count, offset);
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -790,7 +790,7 @@ pub fn create(path: [*]const u8, perm: usize) usize {
 
 // TODO https://github.com/ziglang/zig/issues/265
 pub fn openat(dirfd: i32, path: [*]const u8, flags: usize, mode: usize) usize {
-    return syscall4(SYS_openat, usize(dirfd), @ptrToInt(path), flags, mode);
+    return syscall4(SYS_openat, @intCast(usize, dirfd), @ptrToInt(path), flags, mode);
 }
 
 /// See also `clone` (from the arch-specific include)
@@ -804,11 +804,11 @@ pub fn clone2(flags: usize, child_stack_ptr: usize) usize {
 }
 
 pub fn close(fd: i32) usize {
-    return syscall1(SYS_close, usize(fd));
+    return syscall1(SYS_close, @intCast(usize, fd));
 }
 
 pub fn lseek(fd: i32, offset: isize, ref_pos: usize) usize {
-    return syscall3(SYS_lseek, usize(fd), @bitCast(usize, offset), ref_pos);
+    return syscall3(SYS_lseek, @intCast(usize, fd), @bitCast(usize, offset), ref_pos);
 }
 
 pub fn exit(status: i32) noreturn {
@@ -817,11 +817,11 @@ pub fn exit(status: i32) noreturn {
 }
 
 pub fn getrandom(buf: [*]u8, count: usize, flags: u32) usize {
-    return syscall3(SYS_getrandom, @ptrToInt(buf), count, usize(flags));
+    return syscall3(SYS_getrandom, @ptrToInt(buf), count, @intCast(usize, flags));
 }
 
 pub fn kill(pid: i32, sig: i32) usize {
-    return syscall2(SYS_kill, @bitCast(usize, isize(pid)), usize(sig));
+    return syscall2(SYS_kill, @bitCast(usize, isize(pid)), @intCast(usize, sig));
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -999,8 +999,8 @@ pub const empty_sigset = []usize{0} ** sigset_t.len;
 pub fn raise(sig: i32) usize {
     var set: sigset_t = undefined;
     blockAppSignals(&set);
-    const tid = i32(syscall0(SYS_gettid));
-    const ret = syscall2(SYS_tkill, usize(tid), usize(sig));
+    const tid = @intCast(i32, syscall0(SYS_gettid));
+    const ret = syscall2(SYS_tkill, @intCast(usize, tid), @intCast(usize, sig));
     restoreSignals(&set);
     return ret;
 }
@@ -1019,12 +1019,12 @@ fn restoreSignals(set: *sigset_t) void {
 
 pub fn sigaddset(set: *sigset_t, sig: u6) void {
     const s = sig - 1;
-    (set.*)[usize(s) / usize.bit_count] |= usize(1) << (s & (usize.bit_count - 1));
+    (set.*)[@intCast(usize, s) / usize.bit_count] |= @intCast(usize, 1) << (s & (usize.bit_count - 1));
 }
 
 pub fn sigismember(set: *const sigset_t, sig: u6) bool {
     const s = sig - 1;
-    return ((set.*)[usize(s) / usize.bit_count] & (usize(1) << (s & (usize.bit_count - 1)))) != 0;
+    return ((set.*)[@intCast(usize, s) / usize.bit_count] & (@intCast(usize, 1) << (s & (usize.bit_count - 1)))) != 0;
 }
 
 pub const in_port_t = u16;
@@ -1057,11 +1057,11 @@ pub const iovec = extern struct {
 };
 
 pub fn getsockname(fd: i32, noalias addr: *sockaddr, noalias len: *socklen_t) usize {
-    return syscall3(SYS_getsockname, usize(fd), @ptrToInt(addr), @ptrToInt(len));
+    return syscall3(SYS_getsockname, @intCast(usize, fd), @ptrToInt(addr), @ptrToInt(len));
 }
 
 pub fn getpeername(fd: i32, noalias addr: *sockaddr, noalias len: *socklen_t) usize {
-    return syscall3(SYS_getpeername, usize(fd), @ptrToInt(addr), @ptrToInt(len));
+    return syscall3(SYS_getpeername, @intCast(usize, fd), @ptrToInt(addr), @ptrToInt(len));
 }
 
 pub fn socket(domain: u32, socket_type: u32, protocol: u32) usize {
@@ -1069,47 +1069,47 @@ pub fn socket(domain: u32, socket_type: u32, protocol: u32) usize {
 }
 
 pub fn setsockopt(fd: i32, level: u32, optname: u32, optval: [*]const u8, optlen: socklen_t) usize {
-    return syscall5(SYS_setsockopt, usize(fd), level, optname, usize(optval), @ptrToInt(optlen));
+    return syscall5(SYS_setsockopt, @intCast(usize, fd), level, optname, @intCast(usize, optval), @ptrToInt(optlen));
 }
 
 pub fn getsockopt(fd: i32, level: u32, optname: u32, noalias optval: [*]u8, noalias optlen: *socklen_t) usize {
-    return syscall5(SYS_getsockopt, usize(fd), level, optname, @ptrToInt(optval), @ptrToInt(optlen));
+    return syscall5(SYS_getsockopt, @intCast(usize, fd), level, optname, @ptrToInt(optval), @ptrToInt(optlen));
 }
 
 pub fn sendmsg(fd: i32, msg: *const msghdr, flags: u32) usize {
-    return syscall3(SYS_sendmsg, usize(fd), @ptrToInt(msg), flags);
+    return syscall3(SYS_sendmsg, @intCast(usize, fd), @ptrToInt(msg), flags);
 }
 
 pub fn connect(fd: i32, addr: *const sockaddr, len: socklen_t) usize {
-    return syscall3(SYS_connect, usize(fd), @ptrToInt(addr), usize(len));
+    return syscall3(SYS_connect, @intCast(usize, fd), @ptrToInt(addr), @intCast(usize, len));
 }
 
 pub fn recvmsg(fd: i32, msg: *msghdr, flags: u32) usize {
-    return syscall3(SYS_recvmsg, usize(fd), @ptrToInt(msg), flags);
+    return syscall3(SYS_recvmsg, @intCast(usize, fd), @ptrToInt(msg), flags);
 }
 
 pub fn recvfrom(fd: i32, noalias buf: [*]u8, len: usize, flags: u32, noalias addr: ?*sockaddr, noalias alen: ?*socklen_t) usize {
-    return syscall6(SYS_recvfrom, usize(fd), @ptrToInt(buf), len, flags, @ptrToInt(addr), @ptrToInt(alen));
+    return syscall6(SYS_recvfrom, @intCast(usize, fd), @ptrToInt(buf), len, flags, @ptrToInt(addr), @ptrToInt(alen));
 }
 
 pub fn shutdown(fd: i32, how: i32) usize {
-    return syscall2(SYS_shutdown, usize(fd), usize(how));
+    return syscall2(SYS_shutdown, @intCast(usize, fd), @intCast(usize, how));
 }
 
 pub fn bind(fd: i32, addr: *const sockaddr, len: socklen_t) usize {
-    return syscall3(SYS_bind, usize(fd), @ptrToInt(addr), usize(len));
+    return syscall3(SYS_bind, @intCast(usize, fd), @ptrToInt(addr), @intCast(usize, len));
 }
 
 pub fn listen(fd: i32, backlog: u32) usize {
-    return syscall2(SYS_listen, usize(fd), backlog);
+    return syscall2(SYS_listen, @intCast(usize, fd), backlog);
 }
 
 pub fn sendto(fd: i32, buf: [*]const u8, len: usize, flags: u32, addr: ?*const sockaddr, alen: socklen_t) usize {
-    return syscall6(SYS_sendto, usize(fd), @ptrToInt(buf), len, flags, @ptrToInt(addr), usize(alen));
+    return syscall6(SYS_sendto, @intCast(usize, fd), @ptrToInt(buf), len, flags, @ptrToInt(addr), @intCast(usize, alen));
 }
 
 pub fn socketpair(domain: i32, socket_type: i32, protocol: i32, fd: [2]i32) usize {
-    return syscall4(SYS_socketpair, usize(domain), usize(socket_type), usize(protocol), @ptrToInt(*fd[0]));
+    return syscall4(SYS_socketpair, @intCast(usize, domain), @intCast(usize, socket_type), @intCast(usize, protocol), @ptrToInt(*fd[0]));
 }
 
 pub fn accept(fd: i32, noalias addr: *sockaddr, noalias len: *socklen_t) usize {
@@ -1117,11 +1117,11 @@ pub fn accept(fd: i32, noalias addr: *sockaddr, noalias len: *socklen_t) usize {
 }
 
 pub fn accept4(fd: i32, noalias addr: *sockaddr, noalias len: *socklen_t, flags: u32) usize {
-    return syscall4(SYS_accept4, usize(fd), @ptrToInt(addr), @ptrToInt(len), flags);
+    return syscall4(SYS_accept4, @intCast(usize, fd), @ptrToInt(addr), @ptrToInt(len), flags);
 }
 
 pub fn fstat(fd: i32, stat_buf: *Stat) usize {
-    return syscall2(SYS_fstat, usize(fd), @ptrToInt(stat_buf));
+    return syscall2(SYS_fstat, @intCast(usize, fd), @ptrToInt(stat_buf));
 }
 
 // TODO https://github.com/ziglang/zig/issues/265
@@ -1214,15 +1214,15 @@ pub fn epoll_create1(flags: usize) usize {
 }
 
 pub fn epoll_ctl(epoll_fd: i32, op: u32, fd: i32, ev: *epoll_event) usize {
-    return syscall4(SYS_epoll_ctl, usize(epoll_fd), usize(op), usize(fd), @ptrToInt(ev));
+    return syscall4(SYS_epoll_ctl, @intCast(usize, epoll_fd), @intCast(usize, op), @intCast(usize, fd), @ptrToInt(ev));
 }
 
 pub fn epoll_wait(epoll_fd: i32, events: [*]epoll_event, maxevents: u32, timeout: i32) usize {
-    return syscall4(SYS_epoll_wait, usize(epoll_fd), @ptrToInt(events), usize(maxevents), usize(timeout));
+    return syscall4(SYS_epoll_wait, @intCast(usize, epoll_fd), @ptrToInt(events), @intCast(usize, maxevents), @intCast(usize, timeout));
 }
 
 pub fn timerfd_create(clockid: i32, flags: u32) usize {
-    return syscall2(SYS_timerfd_create, usize(clockid), usize(flags));
+    return syscall2(SYS_timerfd_create, @intCast(usize, clockid), @intCast(usize, flags));
 }
 
 pub const itimerspec = extern struct {
@@ -1231,11 +1231,11 @@ pub const itimerspec = extern struct {
 };
 
 pub fn timerfd_gettime(fd: i32, curr_value: *itimerspec) usize {
-    return syscall2(SYS_timerfd_gettime, usize(fd), @ptrToInt(curr_value));
+    return syscall2(SYS_timerfd_gettime, @intCast(usize, fd), @ptrToInt(curr_value));
 }
 
 pub fn timerfd_settime(fd: i32, flags: u32, new_value: *const itimerspec, old_value: ?*itimerspec) usize {
-    return syscall4(SYS_timerfd_settime, usize(fd), usize(flags), @ptrToInt(new_value), @ptrToInt(old_value));
+    return syscall4(SYS_timerfd_settime, @intCast(usize, fd), @intCast(usize, flags), @ptrToInt(new_value), @ptrToInt(old_value));
 }
 
 pub const _LINUX_CAPABILITY_VERSION_1 = 0x19980330;
@@ -1345,7 +1345,7 @@ pub const cap_user_data_t = extern struct {
 };
 
 pub fn unshare(flags: usize) usize {
-    return syscall1(SYS_unshare, usize(flags));
+    return syscall1(SYS_unshare, @intCast(usize, flags));
 }
 
 pub fn capget(hdrp: *cap_user_header_t, datap: *cap_user_data_t) usize {
std/os/linux/test.zig
@@ -21,7 +21,7 @@ test "timer" {
         .it_value = time_interval,
     };
 
-    err = linux.timerfd_settime(i32(timer_fd), 0, &new_time, null);
+    err = linux.timerfd_settime(@intCast(i32, timer_fd), 0, &new_time, null);
     assert(err == 0);
 
     var event = linux.epoll_event{
@@ -29,12 +29,12 @@ test "timer" {
         .data = linux.epoll_data{ .ptr = 0 },
     };
 
-    err = linux.epoll_ctl(i32(epoll_fd), linux.EPOLL_CTL_ADD, i32(timer_fd), &event);
+    err = linux.epoll_ctl(@intCast(i32, epoll_fd), linux.EPOLL_CTL_ADD, @intCast(i32, timer_fd), &event);
     assert(err == 0);
 
     const events_one: linux.epoll_event = undefined;
     var events = []linux.epoll_event{events_one} ** 8;
 
     // TODO implicit cast from *[N]T to [*]T
-    err = linux.epoll_wait(i32(epoll_fd), @ptrCast([*]linux.epoll_event, &events), 8, -1);
+    err = linux.epoll_wait(@intCast(i32, epoll_fd), @ptrCast([*]linux.epoll_event, &events), 8, -1);
 }
std/os/linux/vdso.zig
@@ -62,8 +62,8 @@ pub fn lookup(vername: []const u8, name: []const u8) usize {
 
     var i: usize = 0;
     while (i < hashtab[1]) : (i += 1) {
-        if (0 == (u32(1) << u5(syms[i].st_info & 0xf) & OK_TYPES)) continue;
-        if (0 == (u32(1) << u5(syms[i].st_info >> 4) & OK_BINDS)) continue;
+        if (0 == (u32(1) << @intCast(u5, syms[i].st_info & 0xf) & OK_TYPES)) continue;
+        if (0 == (u32(1) << @intCast(u5, syms[i].st_info >> 4) & OK_BINDS)) continue;
         if (0 == syms[i].st_shndx) continue;
         if (!mem.eql(u8, name, cstr.toSliceConst(strings + syms[i].st_name))) continue;
         if (maybe_versym) |versym| {
std/os/windows/util.zig
@@ -42,7 +42,7 @@ pub const WriteError = error{
 };
 
 pub fn windowsWrite(handle: windows.HANDLE, bytes: []const u8) WriteError!void {
-    if (windows.WriteFile(handle, @ptrCast(*const c_void, bytes.ptr), u32(bytes.len), null, null) == 0) {
+    if (windows.WriteFile(handle, @ptrCast(*const c_void, bytes.ptr), @intCast(u32, bytes.len), null, null) == 0) {
         const err = windows.GetLastError();
         return switch (err) {
             windows.ERROR.INVALID_USER_BUFFER => WriteError.SystemResources,
@@ -68,7 +68,12 @@ pub fn windowsIsCygwinPty(handle: windows.HANDLE) bool {
     const size = @sizeOf(windows.FILE_NAME_INFO);
     var name_info_bytes align(@alignOf(windows.FILE_NAME_INFO)) = []u8{0} ** (size + windows.MAX_PATH);
 
-    if (windows.GetFileInformationByHandleEx(handle, windows.FileNameInfo, @ptrCast(*c_void, &name_info_bytes[0]), u32(name_info_bytes.len)) == 0) {
+    if (windows.GetFileInformationByHandleEx(
+        handle,
+        windows.FileNameInfo,
+        @ptrCast(*c_void, &name_info_bytes[0]),
+        @intCast(u32, name_info_bytes.len),
+    ) == 0) {
         return true;
     }
 
std/os/child_process.zig
@@ -413,7 +413,7 @@ pub const ChildProcess = struct {
         }
 
         // we are the parent
-        const pid = i32(pid_result);
+        const pid = @intCast(i32, pid_result);
         if (self.stdin_behavior == StdIo.Pipe) {
             self.stdin = os.File.openHandle(stdin_pipe[1]);
         } else {
std/os/darwin.zig
@@ -290,7 +290,7 @@ pub fn WIFSIGNALED(x: i32) bool {
 /// Get the errno from a syscall return value, or 0 for no error.
 pub fn getErrno(r: usize) usize {
     const signed_r = @bitCast(isize, r);
-    return if (signed_r > -4096 and signed_r < 0) usize(-signed_r) else 0;
+    return if (signed_r > -4096 and signed_r < 0) @intCast(usize, -signed_r) else 0;
 }
 
 pub fn close(fd: i32) usize {
@@ -339,7 +339,14 @@ pub fn write(fd: i32, buf: [*]const u8, nbyte: usize) usize {
 }
 
 pub fn mmap(address: ?[*]u8, length: usize, prot: usize, flags: u32, fd: i32, offset: isize) usize {
-    const ptr_result = c.mmap(@ptrCast(*c_void, address), length, @bitCast(c_int, c_uint(prot)), @bitCast(c_int, c_uint(flags)), fd, offset);
+    const ptr_result = c.mmap(
+        @ptrCast(*c_void, address),
+        length,
+        @bitCast(c_int, @intCast(c_uint, prot)),
+        @bitCast(c_int, c_uint(flags)),
+        fd,
+        offset,
+    );
     const isize_result = @bitCast(isize, @ptrToInt(ptr_result));
     return errnoWrap(isize_result);
 }
std/os/file.zig
@@ -266,7 +266,7 @@ pub const File = struct {
     pub fn getEndPos(self: *File) !usize {
         if (is_posix) {
             const stat = try os.posixFStat(self.handle);
-            return usize(stat.size);
+            return @intCast(usize, stat.size);
         } else if (is_windows) {
             var file_size: windows.LARGE_INTEGER = undefined;
             if (windows.GetFileSizeEx(self.handle, &file_size) == 0) {
@@ -277,7 +277,7 @@ pub const File = struct {
             }
             if (file_size < 0)
                 return error.Overflow;
-            return math.cast(usize, u64(file_size));
+            return math.cast(usize, @intCast(u64, file_size));
         } else {
             @compileError("TODO support getEndPos on this OS");
         }
@@ -343,7 +343,7 @@ pub const File = struct {
         } else if (is_windows) {
             var index: usize = 0;
             while (index < buffer.len) {
-                const want_read_count = windows.DWORD(math.min(windows.DWORD(@maxValue(windows.DWORD)), buffer.len - index));
+                const want_read_count = @intCast(windows.DWORD, math.min(windows.DWORD(@maxValue(windows.DWORD)), buffer.len - index));
                 var amt_read: windows.DWORD = undefined;
                 if (windows.ReadFile(self.handle, @ptrCast(*c_void, buffer.ptr + index), want_read_count, &amt_read, null) == 0) {
                     const err = windows.GetLastError();
std/os/index.zig
@@ -126,7 +126,7 @@ pub fn getRandomBytes(buf: []u8) !void {
             }
             defer _ = windows.CryptReleaseContext(hCryptProv, 0);
 
-            if (windows.CryptGenRandom(hCryptProv, windows.DWORD(buf.len), buf.ptr) == 0) {
+            if (windows.CryptGenRandom(hCryptProv, @intCast(windows.DWORD, buf.len), buf.ptr) == 0) {
                 const err = windows.GetLastError();
                 return switch (err) {
                     else => unexpectedErrorWindows(err),
@@ -343,7 +343,7 @@ pub fn posixOpenC(file_path: [*]const u8, flags: u32, perm: usize) !i32 {
                 else => return unexpectedErrorPosix(err),
             }
         }
-        return i32(result);
+        return @intCast(i32, result);
     }
 }
 
@@ -586,7 +586,7 @@ pub fn getCwd(allocator: *Allocator) ![]u8 {
             errdefer allocator.free(buf);
 
             while (true) {
-                const result = windows.GetCurrentDirectoryA(windows.WORD(buf.len), buf.ptr);
+                const result = windows.GetCurrentDirectoryA(@intCast(windows.WORD, buf.len), buf.ptr);
 
                 if (result == 0) {
                     const err = windows.GetLastError();
@@ -2019,7 +2019,7 @@ pub fn posixSocket(domain: u32, socket_type: u32, protocol: u32) !i32 {
     const rc = posix.socket(domain, socket_type, protocol);
     const err = posix.getErrno(rc);
     switch (err) {
-        0 => return i32(rc),
+        0 => return @intCast(i32, rc),
         posix.EACCES => return PosixSocketError.PermissionDenied,
         posix.EAFNOSUPPORT => return PosixSocketError.AddressFamilyNotSupported,
         posix.EINVAL => return PosixSocketError.ProtocolFamilyNotAvailable,
@@ -2183,7 +2183,7 @@ pub fn posixAccept(fd: i32, addr: *posix.sockaddr, flags: u32) PosixAcceptError!
         const rc = posix.accept4(fd, addr, &sockaddr_size, flags);
         const err = posix.getErrno(rc);
         switch (err) {
-            0 => return i32(rc),
+            0 => return @intCast(i32, rc),
             posix.EINTR => continue,
             else => return unexpectedErrorPosix(err),
 
@@ -2226,7 +2226,7 @@ pub fn linuxEpollCreate(flags: u32) LinuxEpollCreateError!i32 {
     const rc = posix.epoll_create1(flags);
     const err = posix.getErrno(rc);
     switch (err) {
-        0 => return i32(rc),
+        0 => return @intCast(i32, rc),
         else => return unexpectedErrorPosix(err),
 
         posix.EINVAL => return LinuxEpollCreateError.InvalidSyscall,
@@ -2296,7 +2296,7 @@ pub fn linuxEpollCtl(epfd: i32, op: u32, fd: i32, event: *linux.epoll_event) Lin
 
 pub fn linuxEpollWait(epfd: i32, events: []linux.epoll_event, timeout: i32) usize {
     while (true) {
-        const rc = posix.epoll_wait(epfd, events.ptr, u32(events.len), timeout);
+        const rc = posix.epoll_wait(epfd, events.ptr, @intCast(u32, events.len), timeout);
         const err = posix.getErrno(rc);
         switch (err) {
             0 => return rc,
@@ -2661,7 +2661,7 @@ pub fn spawnThread(context: var, comptime startFn: var) SpawnThreadError!*Thread
             posix.EAGAIN => return SpawnThreadError.SystemResources,
             posix.EPERM => unreachable,
             posix.EINVAL => unreachable,
-            else => return unexpectedErrorPosix(usize(err)),
+            else => return unexpectedErrorPosix(@intCast(usize, err)),
         }
     } else if (builtin.os == builtin.Os.linux) {
         // use linux API directly.  TODO use posix.CLONE_SETTLS and initialize thread local storage correctly
std/os/time.zig
@@ -14,12 +14,12 @@ pub const epoch = @import("epoch.zig");
 pub fn sleep(seconds: usize, nanoseconds: usize) void {
     switch (builtin.os) {
         Os.linux, Os.macosx, Os.ios => {
-            posixSleep(u63(seconds), u63(nanoseconds));
+            posixSleep(@intCast(u63, seconds), @intCast(u63, nanoseconds));
         },
         Os.windows => {
             const ns_per_ms = ns_per_s / ms_per_s;
             const milliseconds = seconds * ms_per_s + nanoseconds / ns_per_ms;
-            windows.Sleep(windows.DWORD(milliseconds));
+            windows.Sleep(@intCast(windows.DWORD, milliseconds));
         },
         else => @compileError("Unsupported OS"),
     }
@@ -83,8 +83,8 @@ fn milliTimestampDarwin() u64 {
     var tv: darwin.timeval = undefined;
     var err = darwin.gettimeofday(&tv, null);
     debug.assert(err == 0);
-    const sec_ms = u64(tv.tv_sec) * ms_per_s;
-    const usec_ms = @divFloor(u64(tv.tv_usec), us_per_s / ms_per_s);
+    const sec_ms = @intCast(u64, tv.tv_sec) * ms_per_s;
+    const usec_ms = @divFloor(@intCast(u64, tv.tv_usec), us_per_s / ms_per_s);
     return u64(sec_ms) + u64(usec_ms);
 }
 
@@ -95,8 +95,8 @@ fn milliTimestampPosix() u64 {
     var ts: posix.timespec = undefined;
     const err = posix.clock_gettime(posix.CLOCK_REALTIME, &ts);
     debug.assert(err == 0);
-    const sec_ms = u64(ts.tv_sec) * ms_per_s;
-    const nsec_ms = @divFloor(u64(ts.tv_nsec), ns_per_s / ms_per_s);
+    const sec_ms = @intCast(u64, ts.tv_sec) * ms_per_s;
+    const nsec_ms = @divFloor(@intCast(u64, ts.tv_nsec), ns_per_s / ms_per_s);
     return sec_ms + nsec_ms;
 }
 
@@ -162,13 +162,13 @@ pub const Timer = struct {
                 var freq: i64 = undefined;
                 var err = windows.QueryPerformanceFrequency(&freq);
                 if (err == windows.FALSE) return error.TimerUnsupported;
-                self.frequency = u64(freq);
+                self.frequency = @intCast(u64, freq);
                 self.resolution = @divFloor(ns_per_s, self.frequency);
 
                 var start_time: i64 = undefined;
                 err = windows.QueryPerformanceCounter(&start_time);
                 debug.assert(err != windows.FALSE);
-                self.start_time = u64(start_time);
+                self.start_time = @intCast(u64, start_time);
             },
             Os.linux => {
                 //On Linux, seccomp can do arbitrary things to our ability to call
@@ -184,12 +184,12 @@ pub const Timer = struct {
                     posix.EINVAL => return error.TimerUnsupported,
                     else => return std.os.unexpectedErrorPosix(errno),
                 }
-                self.resolution = u64(ts.tv_sec) * u64(ns_per_s) + u64(ts.tv_nsec);
+                self.resolution = @intCast(u64, ts.tv_sec) * u64(ns_per_s) + @intCast(u64, ts.tv_nsec);
 
                 result = posix.clock_gettime(monotonic_clock_id, &ts);
                 errno = posix.getErrno(result);
                 if (errno != 0) return std.os.unexpectedErrorPosix(errno);
-                self.start_time = u64(ts.tv_sec) * u64(ns_per_s) + u64(ts.tv_nsec);
+                self.start_time = @intCast(u64, ts.tv_sec) * u64(ns_per_s) + @intCast(u64, ts.tv_nsec);
             },
             Os.macosx, Os.ios => {
                 darwin.mach_timebase_info(&self.frequency);
@@ -236,7 +236,7 @@ pub const Timer = struct {
         var result: i64 = undefined;
         var err = windows.QueryPerformanceCounter(&result);
         debug.assert(err != windows.FALSE);
-        return u64(result);
+        return @intCast(u64, result);
     }
 
     fn clockDarwin() u64 {
@@ -247,7 +247,7 @@ pub const Timer = struct {
         var ts: posix.timespec = undefined;
         var result = posix.clock_gettime(monotonic_clock_id, &ts);
         debug.assert(posix.getErrno(result) == 0);
-        return u64(ts.tv_sec) * u64(ns_per_s) + u64(ts.tv_nsec);
+        return @intCast(u64, ts.tv_sec) * u64(ns_per_s) + @intCast(u64, ts.tv_nsec);
     }
 };
 
std/rand/index.zig
@@ -55,16 +55,16 @@ pub const Random = struct {
         if (T.is_signed) {
             const uint = @IntType(false, T.bit_count);
             if (start >= 0 and end >= 0) {
-                return T(r.range(uint, uint(start), uint(end)));
+                return @intCast(T, r.range(uint, @intCast(uint, start), @intCast(uint, end)));
             } else if (start < 0 and end < 0) {
                 // Can't overflow because the range is over signed ints
                 return math.negateCast(r.range(uint, math.absCast(end), math.absCast(start)) + 1) catch unreachable;
             } else if (start < 0 and end >= 0) {
-                const end_uint = uint(end);
+                const end_uint = @intCast(uint, end);
                 const total_range = math.absCast(start) + end_uint;
                 const value = r.range(uint, 0, total_range);
                 const result = if (value < end_uint) x: {
-                    break :x T(value);
+                    break :x @intCast(T, value);
                 } else if (value == end_uint) x: {
                     break :x start;
                 } else x: {
@@ -213,9 +213,9 @@ pub const Pcg = struct {
         self.s = l *% default_multiplier +% (self.i | 1);
 
         const xor_s = @truncate(u32, ((l >> 18) ^ l) >> 27);
-        const rot = u32(l >> 59);
+        const rot = @intCast(u32, l >> 59);
 
-        return (xor_s >> u5(rot)) | (xor_s << u5((0 -% rot) & 31));
+        return (xor_s >> @intCast(u5, rot)) | (xor_s << @intCast(u5, (0 -% rot) & 31));
     }
 
     fn seed(self: *Pcg, init_s: u64) void {
@@ -322,7 +322,7 @@ pub const Xoroshiro128 = struct {
         inline for (table) |entry| {
             var b: usize = 0;
             while (b < 64) : (b += 1) {
-                if ((entry & (u64(1) << u6(b))) != 0) {
+                if ((entry & (u64(1) << @intCast(u6, b))) != 0) {
                     s0 ^= self.s[0];
                     s1 ^= self.s[1];
                 }
@@ -667,13 +667,13 @@ test "Random range" {
 }
 
 fn testRange(r: *Random, start: i32, end: i32) void {
-    const count = usize(end - start);
+    const count = @intCast(usize, end - start);
     var values_buffer = []bool{false} ** 20;
     const values = values_buffer[0..count];
     var i: usize = 0;
     while (i < count) {
         const value = r.range(i32, start, end);
-        const index = usize(value - start);
+        const index = @intCast(usize, value - start);
         if (!values[index]) {
             i += 1;
             values[index] = true;
std/special/compiler_rt/divti3.zig
@@ -13,7 +13,7 @@ pub extern fn __divti3(a: i128, b: i128) i128 {
 
     const r = udivmod(u128, @bitCast(u128, an), @bitCast(u128, bn), null);
     const s = s_a ^ s_b;
-    return (i128(r) ^ s) -% s;
+    return (@bitCast(i128, r) ^ s) -% s;
 }
 
 pub extern fn __divti3_windows_x86_64(a: *const i128, b: *const i128) void {
std/special/compiler_rt/fixuint.zig
@@ -32,14 +32,14 @@ pub fn fixuint(comptime fp_t: type, comptime fixuint_t: type, a: fp_t) fixuint_t
     const aAbs: rep_t = aRep & absMask;
 
     const sign = if ((aRep & signBit) != 0) i32(-1) else i32(1);
-    const exponent = i32(aAbs >> significandBits) - exponentBias;
+    const exponent = @intCast(i32, aAbs >> significandBits) - exponentBias;
     const significand: rep_t = (aAbs & significandMask) | implicitBit;
 
     // If either the value or the exponent is negative, the result is zero.
     if (sign == -1 or exponent < 0) return 0;
 
     // If the value is too large for the integer type, saturate.
-    if (c_uint(exponent) >= fixuint_t.bit_count) return ~fixuint_t(0);
+    if (@intCast(c_uint, exponent) >= fixuint_t.bit_count) return ~fixuint_t(0);
 
     // If 0 <= exponent < significandBits, right shift to get the result.
     // Otherwise, shift left.
@@ -47,11 +47,11 @@ pub fn fixuint(comptime fp_t: type, comptime fixuint_t: type, a: fp_t) fixuint_t
         // TODO this is a workaround for the mysterious "integer cast truncated bits"
         // happening on the next line
         @setRuntimeSafety(false);
-        return fixuint_t(significand >> Log2Int(rep_t)(significandBits - exponent));
+        return @intCast(fixuint_t, significand >> @intCast(Log2Int(rep_t), significandBits - exponent));
     } else {
         // TODO this is a workaround for the mysterious "integer cast truncated bits"
         // happening on the next line
         @setRuntimeSafety(false);
-        return fixuint_t(significand) << Log2Int(fixuint_t)(exponent - significandBits);
+        return @intCast(fixuint_t, significand) << @intCast(Log2Int(fixuint_t), exponent - significandBits);
     }
 }
std/special/compiler_rt/index.zig
@@ -292,7 +292,7 @@ extern fn __udivmodsi4(a: u32, b: u32, rem: *u32) u32 {
     @setRuntimeSafety(is_test);
 
     const d = __udivsi3(a, b);
-    rem.* = u32(i32(a) -% (i32(d) * i32(b)));
+    rem.* = @bitCast(u32, @bitCast(i32, a) -% (@bitCast(i32, d) * @bitCast(i32, b)));
     return d;
 }
 
@@ -316,12 +316,12 @@ extern fn __udivsi3(n: u32, d: u32) u32 {
     sr += 1;
     // 1 <= sr <= n_uword_bits - 1
     // Not a special case
-    var q: u32 = n << u5(n_uword_bits - sr);
-    var r: u32 = n >> u5(sr);
+    var q: u32 = n << @intCast(u5, n_uword_bits - sr);
+    var r: u32 = n >> @intCast(u5, sr);
     var carry: u32 = 0;
     while (sr > 0) : (sr -= 1) {
         // r:q = ((r:q)  << 1) | carry
-        r = (r << 1) | (q >> u5(n_uword_bits - 1));
+        r = (r << 1) | (q >> @intCast(u5, n_uword_bits - 1));
         q = (q << 1) | carry;
         // carry = 0;
         // if (r.all >= d.all)
@@ -329,8 +329,8 @@ extern fn __udivsi3(n: u32, d: u32) u32 {
         //      r.all -= d.all;
         //      carry = 1;
         // }
-        const s = i32(d -% r -% 1) >> u5(n_uword_bits - 1);
-        carry = u32(s & 1);
+        const s = @intCast(i32, d -% r -% 1) >> @intCast(u5, n_uword_bits - 1);
+        carry = @intCast(u32, s & 1);
         r -= d & @bitCast(u32, s);
     }
     q = (q << 1) | carry;
std/special/compiler_rt/udivmod.zig
@@ -71,7 +71,7 @@ pub fn udivmod(comptime DoubleInt: type, a: DoubleInt, b: DoubleInt, maybe_rem:
                 r[high] = n[high] & (d[high] - 1);
                 rem.* = @ptrCast(*align(@alignOf(SingleInt)) DoubleInt, &r[0]).*; // TODO issue #421
             }
-            return n[high] >> Log2SingleInt(@ctz(d[high]));
+            return n[high] >> @intCast(Log2SingleInt, @ctz(d[high]));
         }
         // K K
         // ---
@@ -88,10 +88,10 @@ pub fn udivmod(comptime DoubleInt: type, a: DoubleInt, b: DoubleInt, maybe_rem:
         // 1 <= sr <= SingleInt.bit_count - 1
         // q.all = a << (DoubleInt.bit_count - sr);
         q[low] = 0;
-        q[high] = n[low] << Log2SingleInt(SingleInt.bit_count - sr);
+        q[high] = n[low] << @intCast(Log2SingleInt, SingleInt.bit_count - sr);
         // r.all = a >> sr;
-        r[high] = n[high] >> Log2SingleInt(sr);
-        r[low] = (n[high] << Log2SingleInt(SingleInt.bit_count - sr)) | (n[low] >> Log2SingleInt(sr));
+        r[high] = n[high] >> @intCast(Log2SingleInt, sr);
+        r[low] = (n[high] << @intCast(Log2SingleInt, SingleInt.bit_count - sr)) | (n[low] >> @intCast(Log2SingleInt, sr));
     } else {
         // d[low] != 0
         if (d[high] == 0) {
@@ -107,8 +107,8 @@ pub fn udivmod(comptime DoubleInt: type, a: DoubleInt, b: DoubleInt, maybe_rem:
                     return a;
                 }
                 sr = @ctz(d[low]);
-                q[high] = n[high] >> Log2SingleInt(sr);
-                q[low] = (n[high] << Log2SingleInt(SingleInt.bit_count - sr)) | (n[low] >> Log2SingleInt(sr));
+                q[high] = n[high] >> @intCast(Log2SingleInt, sr);
+                q[low] = (n[high] << @intCast(Log2SingleInt, SingleInt.bit_count - sr)) | (n[low] >> @intCast(Log2SingleInt, sr));
                 return @ptrCast(*align(@alignOf(SingleInt)) DoubleInt, &q[0]).*; // TODO issue #421
             }
             // K X
@@ -126,15 +126,15 @@ pub fn udivmod(comptime DoubleInt: type, a: DoubleInt, b: DoubleInt, maybe_rem:
             } else if (sr < SingleInt.bit_count) {
                 // 2 <= sr <= SingleInt.bit_count - 1
                 q[low] = 0;
-                q[high] = n[low] << Log2SingleInt(SingleInt.bit_count - sr);
-                r[high] = n[high] >> Log2SingleInt(sr);
-                r[low] = (n[high] << Log2SingleInt(SingleInt.bit_count - sr)) | (n[low] >> Log2SingleInt(sr));
+                q[high] = n[low] << @intCast(Log2SingleInt, SingleInt.bit_count - sr);
+                r[high] = n[high] >> @intCast(Log2SingleInt, sr);
+                r[low] = (n[high] << @intCast(Log2SingleInt, SingleInt.bit_count - sr)) | (n[low] >> @intCast(Log2SingleInt, sr));
             } else {
                 // SingleInt.bit_count + 1 <= sr <= DoubleInt.bit_count - 1
-                q[low] = n[low] << Log2SingleInt(DoubleInt.bit_count - sr);
-                q[high] = (n[high] << Log2SingleInt(DoubleInt.bit_count - sr)) | (n[low] >> Log2SingleInt(sr - SingleInt.bit_count));
+                q[low] = n[low] << @intCast(Log2SingleInt, DoubleInt.bit_count - sr);
+                q[high] = (n[high] << @intCast(Log2SingleInt, DoubleInt.bit_count - sr)) | (n[low] >> @intCast(Log2SingleInt, sr - SingleInt.bit_count));
                 r[high] = 0;
-                r[low] = n[high] >> Log2SingleInt(sr - SingleInt.bit_count);
+                r[low] = n[high] >> @intCast(Log2SingleInt, sr - SingleInt.bit_count);
             }
         } else {
             // K X
@@ -158,9 +158,9 @@ pub fn udivmod(comptime DoubleInt: type, a: DoubleInt, b: DoubleInt, maybe_rem:
                 r[high] = 0;
                 r[low] = n[high];
             } else {
-                r[high] = n[high] >> Log2SingleInt(sr);
-                r[low] = (n[high] << Log2SingleInt(SingleInt.bit_count - sr)) | (n[low] >> Log2SingleInt(sr));
-                q[high] = n[low] << Log2SingleInt(SingleInt.bit_count - sr);
+                r[high] = n[high] >> @intCast(Log2SingleInt, sr);
+                r[low] = (n[high] << @intCast(Log2SingleInt, SingleInt.bit_count - sr)) | (n[low] >> @intCast(Log2SingleInt, sr));
+                q[high] = n[low] << @intCast(Log2SingleInt, SingleInt.bit_count - sr);
             }
         }
     }
@@ -184,8 +184,8 @@ pub fn udivmod(comptime DoubleInt: type, a: DoubleInt, b: DoubleInt, maybe_rem:
         //      carry = 1;
         // }
         r_all = @ptrCast(*align(@alignOf(SingleInt)) DoubleInt, &r[0]).*; // TODO issue #421
-        const s: SignedDoubleInt = SignedDoubleInt(b -% r_all -% 1) >> (DoubleInt.bit_count - 1);
-        carry = u32(s & 1);
+        const s: SignedDoubleInt = @intCast(SignedDoubleInt, b -% r_all -% 1) >> (DoubleInt.bit_count - 1);
+        carry = @intCast(u32, s & 1);
         r_all -= b & @bitCast(DoubleInt, s);
         r = @ptrCast(*[2]SingleInt, &r_all).*; // TODO issue #421
     }
std/special/bootstrap.zig
@@ -80,7 +80,7 @@ extern fn main(c_argc: i32, c_argv: [*][*]u8, c_envp: [*]?[*]u8) i32 {
     var env_count: usize = 0;
     while (c_envp[env_count] != null) : (env_count += 1) {}
     const envp = @ptrCast([*][*]u8, c_envp)[0..env_count];
-    return callMainWithArgs(usize(c_argc), c_argv, envp);
+    return callMainWithArgs(@intCast(usize, c_argc), c_argv, envp);
 }
 
 fn callMain() u8 {
std/special/builtin.zig
@@ -135,9 +135,9 @@ fn generic_fmod(comptime T: type, x: T, y: T) T {
     const mask = if (T == f32) 0xff else 0x7ff;
     var ux = @bitCast(uint, x);
     var uy = @bitCast(uint, y);
-    var ex = i32((ux >> digits) & mask);
-    var ey = i32((uy >> digits) & mask);
-    const sx = if (T == f32) u32(ux & 0x80000000) else i32(ux >> bits_minus_1);
+    var ex = @intCast(i32, (ux >> digits) & mask);
+    var ey = @intCast(i32, (uy >> digits) & mask);
+    const sx = if (T == f32) @intCast(u32, ux & 0x80000000) else @intCast(i32, ux >> bits_minus_1);
     var i: uint = undefined;
 
     if (uy << 1 == 0 or isNan(uint, uy) or ex == mask)
@@ -156,7 +156,7 @@ fn generic_fmod(comptime T: type, x: T, y: T) T {
             ex -= 1;
             i <<= 1;
         }) {}
-        ux <<= log2uint(@bitCast(u32, -ex + 1));
+        ux <<= @intCast(log2uint, @bitCast(u32, -ex + 1));
     } else {
         ux &= @maxValue(uint) >> exp_bits;
         ux |= 1 << digits;
@@ -167,7 +167,7 @@ fn generic_fmod(comptime T: type, x: T, y: T) T {
             ey -= 1;
             i <<= 1;
         }) {}
-        uy <<= log2uint(@bitCast(u32, -ey + 1));
+        uy <<= @intCast(log2uint, @bitCast(u32, -ey + 1));
     } else {
         uy &= @maxValue(uint) >> exp_bits;
         uy |= 1 << digits;
@@ -199,12 +199,12 @@ fn generic_fmod(comptime T: type, x: T, y: T) T {
         ux -%= 1 << digits;
         ux |= uint(@bitCast(u32, ex)) << digits;
     } else {
-        ux >>= log2uint(@bitCast(u32, -ex + 1));
+        ux >>= @intCast(log2uint, @bitCast(u32, -ex + 1));
     }
     if (T == f32) {
         ux |= sx;
     } else {
-        ux |= uint(sx) << bits_minus_1;
+        ux |= @intCast(uint, sx) << bits_minus_1;
     }
     return @bitCast(T, ux);
 }
@@ -227,8 +227,8 @@ export fn sqrt(x: f64) f64 {
     const sign: u32 = 0x80000000;
     const u = @bitCast(u64, x);
 
-    var ix0 = u32(u >> 32);
-    var ix1 = u32(u & 0xFFFFFFFF);
+    var ix0 = @intCast(u32, u >> 32);
+    var ix1 = @intCast(u32, u & 0xFFFFFFFF);
 
     // sqrt(nan) = nan, sqrt(+inf) = +inf, sqrt(-inf) = nan
     if (ix0 & 0x7FF00000 == 0x7FF00000) {
@@ -245,7 +245,7 @@ export fn sqrt(x: f64) f64 {
     }
 
     // normalize x
-    var m = i32(ix0 >> 20);
+    var m = @intCast(i32, ix0 >> 20);
     if (m == 0) {
         // subnormal
         while (ix0 == 0) {
@@ -259,9 +259,9 @@ export fn sqrt(x: f64) f64 {
         while (ix0 & 0x00100000 == 0) : (i += 1) {
             ix0 <<= 1;
         }
-        m -= i32(i) - 1;
-        ix0 |= ix1 >> u5(32 - i);
-        ix1 <<= u5(i);
+        m -= @intCast(i32, i) - 1;
+        ix0 |= ix1 >> @intCast(u5, 32 - i);
+        ix1 <<= @intCast(u5, i);
     }
 
     // unbias exponent
@@ -345,10 +345,10 @@ export fn sqrt(x: f64) f64 {
 
     // NOTE: musl here appears to rely on signed twos-complement wraparound. +% has the same
     // behaviour at least.
-    var iix0 = i32(ix0);
+    var iix0 = @intCast(i32, ix0);
     iix0 = iix0 +% (m << 20);
 
-    const uz = (u64(iix0) << 32) | ix1;
+    const uz = (@intCast(u64, iix0) << 32) | ix1;
     return @bitCast(f64, uz);
 }
 
std/zig/tokenizer.zig
@@ -1128,7 +1128,7 @@ pub const Tokenizer = struct {
             // check utf8-encoded character.
             const length = std.unicode.utf8ByteSequenceLength(c0) catch return 1;
             if (self.index + length > self.buffer.len) {
-                return u3(self.buffer.len - self.index);
+                return @intCast(u3, self.buffer.len - self.index);
             }
             const bytes = self.buffer[self.index .. self.index + length];
             switch (length) {
std/array_list.zig
@@ -185,23 +185,23 @@ test "basic ArrayList test" {
     {
         var i: usize = 0;
         while (i < 10) : (i += 1) {
-            list.append(i32(i + 1)) catch unreachable;
+            list.append(@intCast(i32, i + 1)) catch unreachable;
         }
     }
 
     {
         var i: usize = 0;
         while (i < 10) : (i += 1) {
-            assert(list.items[i] == i32(i + 1));
+            assert(list.items[i] == @intCast(i32, i + 1));
         }
     }
 
     for (list.toSlice()) |v, i| {
-        assert(v == i32(i + 1));
+        assert(v == @intCast(i32, i + 1));
     }
 
     for (list.toSliceConst()) |v, i| {
-        assert(v == i32(i + 1));
+        assert(v == @intCast(i32, i + 1));
     }
 
     assert(list.pop() == 10);
std/base64.zig
@@ -99,7 +99,7 @@ pub const Base64Decoder = struct {
             assert(!result.char_in_alphabet[c]);
             assert(c != pad_char);
 
-            result.char_to_index[c] = u8(i);
+            result.char_to_index[c] = @intCast(u8, i);
             result.char_in_alphabet[c] = true;
         }
 
@@ -284,7 +284,7 @@ pub const Base64DecoderUnsafe = struct {
         };
         for (alphabet_chars) |c, i| {
             assert(c != pad_char);
-            result.char_to_index[c] = u8(i);
+            result.char_to_index[c] = @intCast(u8, i);
         }
         return result;
     }
std/heap.zig
@@ -408,7 +408,7 @@ fn testAllocator(allocator: *mem.Allocator) !void {
 
     for (slice) |*item, i| {
         item.* = try allocator.create(i32);
-        item.*.* = i32(i);
+        item.*.* = @intCast(i32, i);
     }
 
     for (slice) |item, i| {
std/json.zig
@@ -180,7 +180,7 @@ pub const StreamingParser = struct {
         pub fn fromInt(x: var) State {
             debug.assert(x == 0 or x == 1);
             const T = @TagType(State);
-            return State(T(x));
+            return State(@intCast(T, x));
         }
     };
 
std/mem.zig
@@ -334,7 +334,7 @@ pub fn readInt(bytes: []const u8, comptime T: type, endian: builtin.Endian) T {
         builtin.Endian.Little => {
             const ShiftType = math.Log2Int(T);
             for (bytes) |b, index| {
-                result = result | (T(b) << ShiftType(index * 8));
+                result = result | (T(b) << @intCast(ShiftType, index * 8));
             }
         },
     }
std/segmented_list.zig
@@ -104,7 +104,7 @@ pub fn SegmentedList(comptime T: type, comptime prealloc_item_count: usize) type
         }
 
         pub fn deinit(self: *Self) void {
-            self.freeShelves(ShelfIndex(self.dynamic_segments.len), 0);
+            self.freeShelves(@intCast(ShelfIndex, self.dynamic_segments.len), 0);
             self.allocator.free(self.dynamic_segments);
             self.* = undefined;
         }
@@ -158,7 +158,7 @@ pub fn SegmentedList(comptime T: type, comptime prealloc_item_count: usize) type
         /// Only grows capacity, or retains current capacity
         pub fn growCapacity(self: *Self, new_capacity: usize) !void {
             const new_cap_shelf_count = shelfCount(new_capacity);
-            const old_shelf_count = ShelfIndex(self.dynamic_segments.len);
+            const old_shelf_count = @intCast(ShelfIndex, self.dynamic_segments.len);
             if (new_cap_shelf_count > old_shelf_count) {
                 self.dynamic_segments = try self.allocator.realloc([*]T, self.dynamic_segments, new_cap_shelf_count);
                 var i = old_shelf_count;
@@ -175,7 +175,7 @@ pub fn SegmentedList(comptime T: type, comptime prealloc_item_count: usize) type
         /// Only shrinks capacity or retains current capacity
         pub fn shrinkCapacity(self: *Self, new_capacity: usize) void {
             if (new_capacity <= prealloc_item_count) {
-                const len = ShelfIndex(self.dynamic_segments.len);
+                const len = @intCast(ShelfIndex, self.dynamic_segments.len);
                 self.freeShelves(len, 0);
                 self.allocator.free(self.dynamic_segments);
                 self.dynamic_segments = [][*]T{};
@@ -183,7 +183,7 @@ pub fn SegmentedList(comptime T: type, comptime prealloc_item_count: usize) type
             }
 
             const new_cap_shelf_count = shelfCount(new_capacity);
-            const old_shelf_count = ShelfIndex(self.dynamic_segments.len);
+            const old_shelf_count = @intCast(ShelfIndex, self.dynamic_segments.len);
             assert(new_cap_shelf_count <= old_shelf_count);
             if (new_cap_shelf_count == old_shelf_count) {
                 return;
@@ -338,7 +338,7 @@ fn testSegmentedList(comptime prealloc: usize, allocator: *Allocator) !void {
     {
         var i: usize = 0;
         while (i < 100) : (i += 1) {
-            try list.push(i32(i + 1));
+            try list.push(@intCast(i32, i + 1));
             assert(list.len == i + 1);
         }
     }
@@ -346,7 +346,7 @@ fn testSegmentedList(comptime prealloc: usize, allocator: *Allocator) !void {
     {
         var i: usize = 0;
         while (i < 100) : (i += 1) {
-            assert(list.at(i).* == i32(i + 1));
+            assert(list.at(i).* == @intCast(i32, i + 1));
         }
     }
 
std/unicode.zig
@@ -35,22 +35,22 @@ pub fn utf8Encode(c: u32, out: []u8) !u3 {
         // - Increasing the initial shift by 6 each time
         // - Each time after the first shorten the shifted
         //   value to a max of 0b111111 (63)
-        1 => out[0] = u8(c), // Can just do 0 + codepoint for initial range
+        1 => out[0] = @intCast(u8, c), // Can just do 0 + codepoint for initial range
         2 => {
-            out[0] = u8(0b11000000 | (c >> 6));
-            out[1] = u8(0b10000000 | (c & 0b111111));
+            out[0] = @intCast(u8, 0b11000000 | (c >> 6));
+            out[1] = @intCast(u8, 0b10000000 | (c & 0b111111));
         },
         3 => {
             if (0xd800 <= c and c <= 0xdfff) return error.Utf8CannotEncodeSurrogateHalf;
-            out[0] = u8(0b11100000 | (c >> 12));
-            out[1] = u8(0b10000000 | ((c >> 6) & 0b111111));
-            out[2] = u8(0b10000000 | (c & 0b111111));
+            out[0] = @intCast(u8, 0b11100000 | (c >> 12));
+            out[1] = @intCast(u8, 0b10000000 | ((c >> 6) & 0b111111));
+            out[2] = @intCast(u8, 0b10000000 | (c & 0b111111));
         },
         4 => {
-            out[0] = u8(0b11110000 | (c >> 18));
-            out[1] = u8(0b10000000 | ((c >> 12) & 0b111111));
-            out[2] = u8(0b10000000 | ((c >> 6) & 0b111111));
-            out[3] = u8(0b10000000 | (c & 0b111111));
+            out[0] = @intCast(u8, 0b11110000 | (c >> 18));
+            out[1] = @intCast(u8, 0b10000000 | ((c >> 12) & 0b111111));
+            out[2] = @intCast(u8, 0b10000000 | ((c >> 6) & 0b111111));
+            out[3] = @intCast(u8, 0b10000000 | (c & 0b111111));
         },
         else => unreachable,
     }
test/cases/cast.zig
@@ -343,7 +343,7 @@ fn testPeerErrorAndArray2(x: u8) error![]const u8 {
 test "explicit cast float number literal to integer if no fraction component" {
     const x = i32(1e4);
     assert(x == 10000);
-    const y = i32(f32(1e4));
+    const y = @floatToInt(i32, f32(1e4));
     assert(y == 10000);
 }
 
@@ -398,3 +398,19 @@ test "cast *[1][*]const u8 to [*]const ?[*]const u8" {
     const x: [*]const ?[*]const u8 = &window_name;
     assert(mem.eql(u8, std.cstr.toSliceConst(x[0].?), "window name"));
 }
+
+test "@intCast comptime_int" {
+    const result = @intCast(i32, 1234);
+    assert(@typeOf(result) == i32);
+    assert(result == 1234);
+}
+
+test "@floatCast comptime_int and comptime_float" {
+    const result = @floatCast(f32, 1234);
+    assert(@typeOf(result) == f32);
+    assert(result == 1234.0);
+
+    const result2 = @floatCast(f32, 1234.0);
+    assert(@typeOf(result) == f32);
+    assert(result == 1234.0);
+}
test/cases/enum.zig
@@ -99,7 +99,7 @@ test "int to enum" {
     testIntToEnumEval(3);
 }
 fn testIntToEnumEval(x: i32) void {
-    assert(IntToEnumNumber(u3(x)) == IntToEnumNumber.Three);
+    assert(IntToEnumNumber(@intCast(u3, x)) == IntToEnumNumber.Three);
 }
 const IntToEnumNumber = enum {
     Zero,
test/cases/eval.zig
@@ -5,7 +5,7 @@ const builtin = @import("builtin");
 test "compile time recursion" {
     assert(some_data.len == 21);
 }
-var some_data: [usize(fibonacci(7))]u8 = undefined;
+var some_data: [@intCast(usize, fibonacci(7))]u8 = undefined;
 fn fibonacci(x: i32) i32 {
     if (x <= 1) return 1;
     return fibonacci(x - 1) + fibonacci(x - 2);
@@ -356,7 +356,7 @@ const global_array = x: {
 test "compile-time downcast when the bits fit" {
     comptime {
         const spartan_count: u16 = 255;
-        const byte = u8(spartan_count);
+        const byte = @intCast(u8, spartan_count);
         assert(byte == 255);
     }
 }
@@ -440,7 +440,7 @@ test "binary math operator in partially inlined function" {
     var b: [16]u8 = undefined;
 
     for (b) |*r, i|
-        r.* = u8(i + 1);
+        r.* = @intCast(u8, i + 1);
 
     copyWithPartialInline(s[0..], b[0..]);
     assert(s[0] == 0x1020304);
@@ -480,7 +480,7 @@ fn generateTable(comptime T: type) [1010]T {
     var res: [1010]T = undefined;
     var i: usize = 0;
     while (i < 1010) : (i += 1) {
-        res[i] = T(i);
+        res[i] = @intCast(T, i);
     }
     return res;
 }
test/cases/fn.zig
@@ -80,7 +80,7 @@ test "function pointers" {
         fn4,
     };
     for (fns) |f, i| {
-        assert(f() == u32(i) + 5);
+        assert(f() == @intCast(u32, i) + 5);
     }
 }
 fn fn1() u32 {
test/cases/for.zig
@@ -46,7 +46,7 @@ test "basic for loop" {
         buf_index += 1;
     }
     for (array) |item, index| {
-        buffer[buf_index] = u8(index);
+        buffer[buf_index] = @intCast(u8, index);
         buf_index += 1;
     }
     const unknown_size: []const u8 = array;
@@ -55,7 +55,7 @@ test "basic for loop" {
         buf_index += 1;
     }
     for (unknown_size) |item, index| {
-        buffer[buf_index] = u8(index);
+        buffer[buf_index] = @intCast(u8, index);
         buf_index += 1;
     }
 
test/cases/struct.zig
@@ -365,14 +365,14 @@ test "runtime struct initialization of bitfield" {
         .y = x1,
     };
     const s2 = Nibbles{
-        .x = u4(x2),
-        .y = u4(x2),
+        .x = @intCast(u4, x2),
+        .y = @intCast(u4, x2),
     };
 
     assert(s1.x == x1);
     assert(s1.y == x1);
-    assert(s2.x == u4(x2));
-    assert(s2.y == u4(x2));
+    assert(s2.x == @intCast(u4, x2));
+    assert(s2.y == @intCast(u4, x2));
 }
 
 var x1 = u4(1);