Vendor import of llvm trunk r154661:

http://llvm.org/svn/llvm-project/llvm/trunk@r154661

1 files changed, 21 insertions, 6 deletions

diff --git a/include/llvm/Support/Compiler.h b/include/llvm/Support/Compiler.h
index e092157..d0b186e 100644
--- a/include/llvm/Support/Compiler.h
+++ b/include/llvm/Support/Compiler.h
@@ -49,16 +49,22 @@
 #define LLVM_ATTRIBUTE_UNUSED
 #endif
 
-#ifdef __GNUC__ // aka 'ATTRIBUTE_CONST' but following LLVM Conventions.
-#define LLVM_ATTRIBUTE_READNONE __attribute__((__const__))
+#if (__GNUC__ >= 4) && !defined(__MINGW32__) && !defined(__CYGWIN__)
+#define LLVM_ATTRIBUTE_WEAK __attribute__((__weak__))
 #else
-#define LLVM_ATTRIBUTE_READNONE
+#define LLVM_ATTRIBUTE_WEAK
 #endif
 
-#ifdef __GNUC__  // aka 'ATTRIBUTE_PURE' but following LLVM Conventions.
-#define LLVM_ATTRIBUTE_READONLY __attribute__((__pure__))
+#ifdef __GNUC__ // aka 'CONST' but following LLVM Conventions.
+#define LLVM_READNONE __attribute__((__const__))
 #else
-#define LLVM_ATTRIBUTE_READONLY
+#define LLVM_READNONE
+#endif
+
+#ifdef __GNUC__  // aka 'PURE' but following LLVM Conventions.
+#define LLVM_READONLY __attribute__((__pure__))
+#else
+#define LLVM_READONLY
 #endif
 
 #if (__GNUC__ >= 4)
@@ -67,6 +73,7 @@
 #define BUILTIN_EXPECT(EXPR, VALUE) (EXPR)
 #endif
 
+
 // C++ doesn't support 'extern template' of template specializations.  GCC does,
 // but requires __extension__ before it.  In the header, use this:
 //   EXTERN_TEMPLATE_INSTANTIATION(class foo<bar>);
@@ -111,6 +118,14 @@
 #define LLVM_ATTRIBUTE_NORETURN
 #endif
 
+// LLVM_EXTENSION - Support compilers where we have a keyword to suppress
+// pedantic diagnostics.
+#ifdef __GNUC__
+#define LLVM_EXTENSION __extension__
+#else
+#define LLVM_EXTENSION
+#endif
+
 // LLVM_ATTRIBUTE_DEPRECATED(decl, "message")
 #if __has_feature(attribute_deprecated_with_message)
 # define LLVM_ATTRIBUTE_DEPRECATED(decl, message) \