[Basic] Define __declspec for cygwin

Cygwin (and MinGW) targets define __declspec to __attribute__ unless
-fms-extensions is specified.  It turns out that cygwin headers rely on
the existence of this macro.

llvm-svn: 238394

1 files changed, 9 insertions, 5 deletions

diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index a768081e70e..76b5f579508 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -3596,11 +3596,8 @@ public:
 };
 } // end anonymous namespace
 
-static void addMinGWDefines(const LangOptions &Opts, MacroBuilder &Builder) {
-  Builder.defineMacro("__MSVCRT__");
-  Builder.defineMacro("__MINGW32__");
-
-  // Mingw defines __declspec(a) to __attribute__((a)).  Clang supports
+static void addCygMingDefines(const LangOptions &Opts, MacroBuilder &Builder) {
+  // Mingw and cygwin define __declspec(a) to __attribute__((a)).  Clang supports
   // __declspec natively under -fms-extensions, but we define a no-op __declspec
   // macro anyway for pre-processor compatibility.
   if (Opts.MicrosoftExt)
@@ -3623,6 +3620,12 @@ static void addMinGWDefines(const LangOptions &Opts, MacroBuilder &Builder) {
   }
 }
 
+static void addMinGWDefines(const LangOptions &Opts, MacroBuilder &Builder) {
+  Builder.defineMacro("__MSVCRT__");
+  Builder.defineMacro("__MINGW32__");
+  addCygMingDefines(Opts, Builder);
+}
+
 namespace {
 // x86-32 MinGW target
 class MinGWX86_32TargetInfo : public WindowsX86_32TargetInfo {
@@ -3655,6 +3658,7 @@ public:
     Builder.defineMacro("_X86_");
     Builder.defineMacro("__CYGWIN__");
     Builder.defineMacro("__CYGWIN32__");
+    addCygMingDefines(Opts, Builder);
     DefineStd(Builder, "unix", Opts);
     if (Opts.CPlusPlus)
       Builder.defineMacro("_GNU_SOURCE");