AST: Treat inline function declarations in -fms-compatibility as if it were in C++ when in C mode

This essentially fixes PR16766.

llvm-svn: 187586

2 files changed, 12 insertions, 2 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 1b465312cc8..a3718fea338 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -7807,8 +7807,9 @@ GVALinkage ASTContext::GetGVALinkageForFunction(const FunctionDecl *FD) {
 
   if (!FD->isInlined())
     return External;
-    
-  if (!getLangOpts().CPlusPlus || FD->hasAttr<GNUInlineAttr>()) {
+
+  if ((!getLangOpts().CPlusPlus && !getLangOpts().MicrosoftMode) ||
+      FD->hasAttr<GNUInlineAttr>()) {
     // GNU or C99 inline semantics. Determine whether this symbol should be
     // externally visible.
     if (FD->isInlineDefinitionExternallyVisible())
diff --git a/clang/test/CodeGen/inline.c b/clang/test/CodeGen/inline.c
index 442b38000b3..c1a7f0fbae2 100644
--- a/clang/test/CodeGen/inline.c
+++ b/clang/test/CodeGen/inline.c
@@ -51,6 +51,15 @@
 // CHECK3: define available_externally void @_Z13gnu_ei_inlinev()
 // CHECK3: define linkonce_odr i32 @_Z2eiv()
 
+// RUN: echo "MS C Mode tests:"
+// RUN: %clang %s -target i386-unknown-unknown -O1 -emit-llvm -S -o - -std=c99 -fms-compatibility | FileCheck %s --check-prefix=CHECK4
+// CHECK4: define i32 @bar()
+// CHECK4: define void @gnu_inline()
+// CHECK4: define available_externally void @gnu_ei_inline()
+// CHECK4: define linkonce_odr i32 @foo()
+// CHECK4-NOT: unreferenced
+// CHECK4: define linkonce_odr i32 @ei()
+
 extern __inline int ei() { return 123; }
 
 __inline int foo() {