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[Cygwin] va_list must be treated like normal Windows #143115

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Merged
merged 5 commits into from
Jun 10, 2025
Merged

[Cygwin] va_list must be treated like normal Windows #143115

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c64472a
[Cygwin] va_list must be treated like normal Windows
kikairoya May 25, 2025
ac40213
Update clang/lib/Basic/Targets/X86.h
kikairoya Jun 7, 2025
f2b4fae
Merge branch 'main' into cygwin-va_list
kikairoya Jun 7, 2025
820891b
Update clang/test/CodeGen/X86/cygwin-varargs.c
kikairoya Jun 10, 2025
0ee6de6
Merge branch 'main' into cygwin-va_list
kikairoya Jun 10, 2025
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4 changes: 4 additions & 0 deletions clang/lib/Basic/Targets/X86.h
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Original file line number Diff line number Diff line change
Expand Up @@ -997,6 +997,10 @@ class LLVM_LIBRARY_VISIBILITY CygwinX86_64TargetInfo : public X86_64TargetInfo {
if (Opts.CPlusPlus)
Builder.defineMacro("_GNU_SOURCE");
}

BuiltinVaListKind getBuiltinVaListKind() const override {
return TargetInfo::CharPtrBuiltinVaList;
}
};

class LLVM_LIBRARY_VISIBILITY DarwinX86_64TargetInfo
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35 changes: 35 additions & 0 deletions clang/test/CodeGen/X86/cygwin-varargs.c
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@@ -0,0 +1,35 @@
// RUN: %clang_cc1 -triple x86_64-windows-gnu -emit-llvm < %s | FileCheck %s
// RUN: %clang_cc1 -triple x86_64-pc-cygwin -emit-llvm < %s | FileCheck %s

struct foo {
int x;
float y;
char z;
};
// CHECK: %[[STRUCT_FOO:.*]] = type { i32, float, i8 }

void f(int a, ...) {
// CHECK-LABEL: define dso_local void @f
__builtin_va_list ap;
__builtin_va_start(ap, a);
// CHECK: %[[AP:.*]] = alloca ptr
// CHECK: call void @llvm.va_start
int b = __builtin_va_arg(ap, int);
// CHECK: %[[AP_CUR:.*]] = load ptr, ptr %[[AP]]
// CHECK-NEXT: %[[AP_NEXT:.*]] = getelementptr inbounds i8, ptr %[[AP_CUR]], i64 8
// CHECK-NEXT: store ptr %[[AP_NEXT]], ptr %[[AP]]
double _Complex c = __builtin_va_arg(ap, double _Complex);
// CHECK: %[[AP_CUR2:.*]] = load ptr, ptr %[[AP]]
// CHECK-NEXT: %[[AP_NEXT2:.*]] = getelementptr inbounds i8, ptr %[[AP_CUR2]], i64 8
// CHECK-NEXT: store ptr %[[AP_NEXT2]], ptr %[[AP]]
// CHECK-NEXT: load ptr, ptr %[[AP_CUR2]]
struct foo d = __builtin_va_arg(ap, struct foo);
// CHECK: %[[AP_CUR3:.*]] = load ptr, ptr %[[AP]]
// CHECK-NEXT: %[[AP_NEXT3:.*]] = getelementptr inbounds i8, ptr %[[AP_CUR3]], i64 8
// CHECK-NEXT: store ptr %[[AP_NEXT3]], ptr %[[AP]]
__builtin_va_list ap2;
__builtin_va_copy(ap2, ap);
// CHECK: call void @llvm.va_copy
__builtin_va_end(ap);
// CHECK: call void @llvm.va_end
}
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