[clang] 4abcbb0 - [Clang][Cygwin] Use correct mangling rule (#158404)

[via cfe-commits]

Author: Tomohiro Kashiwada
Date: 2025-09-14T00:40:12+03:00
New Revision: 4abcbb053f8adaf48dbfff677e8ccda1f6d52b33

URL: https://github.com/llvm/llvm-project/commit/4abcbb053f8adaf48dbfff677e8ccda1f6d52b33
DIFF: https://github.com/llvm/llvm-project/commit/4abcbb053f8adaf48dbfff677e8ccda1f6d52b33.diff

LOG: [Clang][Cygwin] Use correct mangling rule (#158404)

In
https://github.com/llvm/llvm-project/commit/45ca613c135ea7b5fbc63bff003f20bf20f62081,
whether to mangle names based on calling conventions according to
Microsoft conventions was refactored to a bool in the TargetInfo. Cygwin
targets also require this mangling, but were missed, presumably due to
lack of test coverage of these targets. This commit enables the name
mangling for Cygwin, and also enables test coverage of this mangling on
Cygwin targets.

Added: 
    

Modified: 
    clang/lib/Basic/Targets/X86.h
    clang/test/CodeGen/mangle-windows.c
    clang/test/CodeGenCXX/mangle-windows.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h
index 6e013c95dbf01..d159a7906854c 100644
--- a/clang/lib/Basic/Targets/X86.h
+++ b/clang/lib/Basic/Targets/X86.h
@@ -646,6 +646,7 @@ class LLVM_LIBRARY_VISIBILITY CygwinX86_32TargetInfo : public X86_32TargetInfo {
       : X86_32TargetInfo(Triple, Opts) {
     this->WCharType = TargetInfo::UnsignedShort;
     this->WIntType = TargetInfo::UnsignedInt;
+    this->UseMicrosoftManglingForC = true;
     DoubleAlign = LongLongAlign = 64;
     resetDataLayout("e-m:x-p:32:32-p270:32:32-p271:32:32-p272:64:64-i64:64-"
                     "i128:128-f80:32-n8:16:32-a:0:32-S32",
@@ -983,6 +984,7 @@ class LLVM_LIBRARY_VISIBILITY CygwinX86_64TargetInfo : public X86_64TargetInfo {
       : X86_64TargetInfo(Triple, Opts) {
     this->WCharType = TargetInfo::UnsignedShort;
     this->WIntType = TargetInfo::UnsignedInt;
+    this->UseMicrosoftManglingForC = true;
   }
 
   void getTargetDefines(const LangOptions &Opts,

diff  --git a/clang/test/CodeGen/mangle-windows.c b/clang/test/CodeGen/mangle-windows.c
index 046b1e8815a8a..e1b06e72a9635 100644
--- a/clang/test/CodeGen/mangle-windows.c
+++ b/clang/test/CodeGen/mangle-windows.c
@@ -1,8 +1,10 @@
 // RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-pc-win32 | FileCheck %s
-// RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-mingw32 | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-mingw32  | FileCheck %s
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-cygwin   | FileCheck %s
 // RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-pc-windows-msvc-elf | FileCheck %s --check-prefix=ELF32
 // RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-pc-win32 | FileCheck %s --check-prefix=X64
-// RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-mingw32 | FileCheck %s --check-prefix=X64
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-mingw32  | FileCheck %s --check-prefix=X64
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-cygwin   | FileCheck %s --check-prefix=X64
 // RUN: %clang_cc1 -emit-llvm %s -o - -triple=x86_64-pc-windows-msvc-elf | FileCheck %s --check-prefix=ELF64
 
 // CHECK: target datalayout = "e-m:x-{{.*}}"

diff  --git a/clang/test/CodeGenCXX/mangle-windows.cpp b/clang/test/CodeGenCXX/mangle-windows.cpp
index 3d5a1e9a868ef..737abcf6e3498 100644
--- a/clang/test/CodeGenCXX/mangle-windows.cpp
+++ b/clang/test/CodeGenCXX/mangle-windows.cpp
@@ -4,6 +4,9 @@
 // RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-mingw32 | \
 // RUN:     FileCheck --check-prefix=ITANIUM %s
 
+// RUN: %clang_cc1 -emit-llvm %s -o - -triple=i386-cygwin | \
+// RUN:     FileCheck --check-prefix=ITANIUM %s
+
 void __stdcall f1(void) {}
 // WIN: define dso_local x86_stdcallcc void @"?f1@@YGXXZ"
 // ITANIUM: define dso_local x86_stdcallcc void @"\01__Z2f1v at 0"