From e20cf3d14997c3511e264748c59687a801caa6ed Mon Sep 17 00:00:00 2001
From: Bob Wilson <bob.wilson@apple.com>
Date: Tue, 4 Sep 2012 17:42:53 +0000
Subject: [PATCH] Make sure macros in the include subdirectory are not used
 without being defined.

Rationale: For each preprocessor macro, either the definedness is what's
meaningful, or the value is what's meaningful, or both. If definedness is
meaningful, we should use #ifdef. If the value is meaningful, we should use
and #ifdef interchangeably for the same macro, seems ugly to me, even if
undefined macros are zero if used.

This also has the benefit that including an LLVM header doesn't prevent
you from compiling with -Wundef -Werror.

Patch by John Garvin!
<rdar://problem/12189979>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163148 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm-c/Core.h             | 2 +-
 include/llvm/Support/Compiler.h   | 2 +-
 include/llvm/Support/FileSystem.h | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/llvm-c/Core.h b/include/llvm-c/Core.h
index 441fa4d13ab..6587e770800 100644
--- a/include/llvm-c/Core.h
+++ b/include/llvm-c/Core.h
@@ -2688,7 +2688,7 @@ namespace llvm {
   
   template<typename T>
   inline T **unwrap(LLVMValueRef *Vals, unsigned Length) {
-    #if DEBUG
+    #ifdef DEBUG
     for (LLVMValueRef *I = Vals, *E = Vals + Length; I != E; ++I)
       cast<T>(*I);
     #endif
diff --git a/include/llvm/Support/Compiler.h b/include/llvm/Support/Compiler.h
index 4f5b8f82392..1136ff70c37 100644
--- a/include/llvm/Support/Compiler.h
+++ b/include/llvm/Support/Compiler.h
@@ -24,7 +24,7 @@
 /// does not imply the existence of any other C++ library features.
 #if (__has_feature(cxx_rvalue_references)   \
      || defined(__GXX_EXPERIMENTAL_CXX0X__) \
-     || _MSC_VER >= 1600)
+     || (defined(_MSC_VER) && _MSC_VER >= 1600))
 #define LLVM_USE_RVALUE_REFERENCES 1
 #else
 #define LLVM_USE_RVALUE_REFERENCES 0
diff --git a/include/llvm/Support/FileSystem.h b/include/llvm/Support/FileSystem.h
index bffc234f93d..5d6020502dc 100644
--- a/include/llvm/Support/FileSystem.h
+++ b/include/llvm/Support/FileSystem.h
@@ -40,7 +40,7 @@
 #include <string>
 #include <vector>
 
-#if HAVE_SYS_STAT_H
+#ifdef HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
 
@@ -596,7 +596,7 @@ private:
   mapmode Mode;
   uint64_t Size;
   void *Mapping;
-#if LLVM_ON_WIN32
+#ifdef LLVM_ON_WIN32
   int FileDescriptor;
   void *FileHandle;
   void *FileMappingHandle;