Commit 57f9405a8f
Changed files (6)
src
test
behavior
src/Sema.zig
@@ -8288,6 +8288,7 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
const dest_ty = try sema.resolveType(block, dest_ty_src, extra.lhs);
const operand = try sema.resolveInst(extra.rhs);
+ const operand_ty = sema.typeOf(operand);
switch (dest_ty.zigTypeTag()) {
.AnyFrame,
.ComptimeFloat,
@@ -8310,8 +8311,8 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
const msg = msg: {
const msg = try sema.errMsg(block, dest_ty_src, "cannot @bitCast to '{}'", .{dest_ty.fmt(sema.mod)});
errdefer msg.destroy(sema.gpa);
- switch (sema.typeOf(operand).zigTypeTag()) {
- .Int, .ComptimeInt => try sema.errNote(block, dest_ty_src, msg, "use @intToEnum for type coercion", .{}),
+ switch (operand_ty.zigTypeTag()) {
+ .Int, .ComptimeInt => try sema.errNote(block, dest_ty_src, msg, "use @intToEnum to cast from '{}'", .{operand_ty.fmt(sema.mod)}),
else => {},
}
@@ -8320,9 +8321,20 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
return sema.failWithOwnedErrorMsg(block, msg);
},
- .Pointer => return sema.fail(block, dest_ty_src, "cannot @bitCast to '{}', use @ptrCast to cast to a pointer", .{
- dest_ty.fmt(sema.mod),
- }),
+ .Pointer => {
+ const msg = msg: {
+ const msg = try sema.errMsg(block, dest_ty_src, "cannot @bitCast to '{}'", .{dest_ty.fmt(sema.mod)});
+ errdefer msg.destroy(sema.gpa);
+ switch (operand_ty.zigTypeTag()) {
+ .Int, .ComptimeInt => try sema.errNote(block, dest_ty_src, msg, "use @intToPtr to cast from '{}'", .{operand_ty.fmt(sema.mod)}),
+ .Pointer => try sema.errNote(block, dest_ty_src, msg, "use @ptrCast to cast from '{}'", .{operand_ty.fmt(sema.mod)}),
+ else => {},
+ }
+
+ break :msg msg;
+ };
+ return sema.failWithOwnedErrorMsg(block, msg);
+ },
.Struct, .Union => if (dest_ty.containerLayout() == .Auto) {
const container = switch (dest_ty.zigTypeTag()) {
.Struct => "struct",
@@ -8342,6 +8354,70 @@ fn zirBitcast(sema: *Sema, block: *Block, inst: Zir.Inst.Index) CompileError!Air
.Vector,
=> {},
}
+ switch (operand_ty.zigTypeTag()) {
+ .AnyFrame,
+ .ComptimeFloat,
+ .ComptimeInt,
+ .EnumLiteral,
+ .ErrorSet,
+ .ErrorUnion,
+ .Fn,
+ .Frame,
+ .NoReturn,
+ .Null,
+ .Opaque,
+ .Optional,
+ .Type,
+ .Undefined,
+ .Void,
+ => return sema.fail(block, operand_src, "cannot @bitCast from '{}'", .{operand_ty.fmt(sema.mod)}),
+
+ .Enum => {
+ const msg = msg: {
+ const msg = try sema.errMsg(block, operand_src, "cannot @bitCast from '{}'", .{operand_ty.fmt(sema.mod)});
+ errdefer msg.destroy(sema.gpa);
+ switch (dest_ty.zigTypeTag()) {
+ .Int, .ComptimeInt => try sema.errNote(block, operand_src, msg, "use @enumToInt to cast to '{}'", .{dest_ty.fmt(sema.mod)}),
+ else => {},
+ }
+
+ break :msg msg;
+ };
+ return sema.failWithOwnedErrorMsg(block, msg);
+ },
+ .Pointer => {
+ const msg = msg: {
+ const msg = try sema.errMsg(block, operand_src, "cannot @bitCast from '{}'", .{operand_ty.fmt(sema.mod)});
+ errdefer msg.destroy(sema.gpa);
+ switch (dest_ty.zigTypeTag()) {
+ .Int, .ComptimeInt => try sema.errNote(block, operand_src, msg, "use @ptrToInt to cast to '{}'", .{dest_ty.fmt(sema.mod)}),
+ .Pointer => try sema.errNote(block, operand_src, msg, "use @ptrCast to cast to '{}'", .{dest_ty.fmt(sema.mod)}),
+ else => {},
+ }
+
+ break :msg msg;
+ };
+ return sema.failWithOwnedErrorMsg(block, msg);
+ },
+ .Struct, .Union => if (operand_ty.containerLayout() == .Auto) {
+ const container = switch (operand_ty.zigTypeTag()) {
+ .Struct => "struct",
+ .Union => "union",
+ else => unreachable,
+ };
+ return sema.fail(block, operand_src, "cannot @bitCast from '{}', {s} does not have a guaranteed in-memory layout", .{
+ operand_ty.fmt(sema.mod), container,
+ });
+ },
+ .BoundFn => @panic("TODO remove this type from the language and compiler"),
+
+ .Array,
+ .Bool,
+ .Float,
+ .Int,
+ .Vector,
+ => {},
+ }
return sema.bitCast(block, dest_ty, operand, operand_src);
}
test/behavior/bitcast.zig
@@ -90,22 +90,6 @@ test "nested bitcast" {
comptime try S.foo(42);
}
-test "@bitCast enum to its integer type" {
- const SOCK = enum(c_int) {
- A,
- B,
-
- fn testBitCastExternEnum() !void {
- var SOCK_DGRAM = @This().B;
- var sock_dgram = @bitCast(c_int, SOCK_DGRAM);
- try expect(sock_dgram == 1);
- }
- };
-
- try SOCK.testBitCastExternEnum();
- comptime try SOCK.testBitCastExternEnum();
-}
-
// issue #3010: compiler segfault
test "bitcast literal [4]u8 param to u32" {
const ip = @bitCast(u32, [_]u8{ 255, 255, 255, 255 });
test/cases/compile_errors/stage1/obj/intToPtr_with_misaligned_address.zig
@@ -1,10 +0,0 @@
-pub fn main() void {
- var y = @intToPtr([*]align(4) u8, 5);
- _ = y;
-}
-
-// error
-// backend=stage1
-// target=native
-//
-// tmp.zig:2:13: error: pointer type '[*]align(4) u8' requires aligned address
test/cases/compile_errors/bitCast_to_enum_type.zig
@@ -9,4 +9,4 @@ export fn entry() void {
// target=native
//
// :3:24: error: cannot @bitCast to 'tmp.entry.E'
-// :3:24: note: use @intToEnum for type coercion
+// :3:24: note: use @intToEnum to cast from 'u32'
test/cases/compile_errors/intToPtr_with_misaligned_address.zig
@@ -0,0 +1,10 @@
+pub export fn entry() void {
+ var y = @intToPtr([*]align(4) u8, 5);
+ _ = y;
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :2:39: error: pointer type '[*]align(4) u8' requires aligned address
test/cases/compile_errors/stage1/obj/issue_3818_bitcast_from_parray-slice_to_u16.zig → test/cases/compile_errors/issue_3818_bitcast_from_parray-slice_to_u16.zig
@@ -10,8 +10,10 @@ export fn foo2() void {
}
// error
-// backend=stage1
+// backend=stage2
// target=native
//
-// tmp.zig:3:42: error: unable to @bitCast from pointer type '*[2]u8'
-// tmp.zig:8:32: error: destination type 'u16' has size 2 but source type '[]const u8' has size 16
+// :3:42: error: cannot @bitCast from '*[2]u8'
+// :3:42: note: use @ptrToInt to cast to 'u16'
+// :8:37: error: cannot @bitCast from '[]const u8'
+// :8:37: note: use @ptrToInt to cast to 'u16'