Commit 865b53f286

@@ -12993,6 +12993,7 @@ static TypeTableEntry *ir_analyze_instruction_alignof(IrAnalyze *ira, IrInstruct
         return ira->codegen->builtin_types.entry_invalid;
     TypeTableEntry *type_entry = ir_resolve_type(ira, type_value);
 
+    ensure_complete_type(ira->codegen, type_entry);
     if (type_is_invalid(type_entry)) {
         return ira->codegen->builtin_types.entry_invalid;
     } else if (type_entry->id == TypeTableEntryIdUnreachable) {
@@ -13000,7 +13001,7 @@ static TypeTableEntry *ir_analyze_instruction_alignof(IrAnalyze *ira, IrInstruct
                 buf_sprintf("no align available for type '%s'", buf_ptr(&type_entry->name)));
         return ira->codegen->builtin_types.entry_invalid;
     } else {
-        uint64_t align_in_bytes = LLVMABISizeOfType(ira->codegen->target_data_ref, type_entry->type_ref);
+        uint64_t align_in_bytes = LLVMABIAlignmentOfType(ira->codegen->target_data_ref, type_entry->type_ref);
         ConstExprValue *out_val = ir_build_const_from(ira, &instruction->base);
         bignum_init_unsigned(&out_val->data.x_bignum, align_in_bytes);
         return ira->codegen->builtin_types.entry_num_lit_int;

@@ -0,0 +1,11 @@
+const assert = @import("std").debug.assert;
+const builtin = @import("builtin");
+
+const Foo = struct { x: u32, y: u32, z: u32, };
+
+test "@alignOf(T) before referencing T" {
+    comptime assert(@alignOf(Foo) != @maxValue(usize));
+    if (builtin.arch == builtin.Arch.x86_64) {
+        comptime assert(@alignOf(Foo) == 4);
+    }
+}

@@ -1,4 +1,5 @@
 comptime {
+    _ = @import("cases/alignof.zig");
     _ = @import("cases/array.zig");
     _ = @import("cases/asm.zig");
     _ = @import("cases/atomics.zig");