[Frontend] Add an ExternCSystem include entry group.

 - The only group where it makes sense for the "ExternC" bit is System, so this
   simplifies having to have the extra isCXXAware (or ImplicitExternC, depending
   on what code you talk to) bit caried around.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173859 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 7 deletions

diff --git a/include/clang/Lex/HeaderSearchOptions.h b/include/clang/Lex/HeaderSearchOptions.h
index 52885635e4..006bf4357b 100644
--- a/include/clang/Lex/HeaderSearchOptions.h
+++ b/include/clang/Lex/HeaderSearchOptions.h
@@ -28,6 +28,8 @@ namespace frontend {
     IndexHeaderMap, ///< Like Angled, but marks header maps used when
                        ///  building frameworks.
     System,         ///< Like Angled, but marks system directories.
+    ExternCSystem,  ///< Like System, but headers are implicitly wrapped in
+                    ///  extern "C".
     CSystem,        ///< Like System, but only used for C.
     CXXSystem,      ///< Like System, but only used for C++.
     ObjCSystem,     ///< Like System, but only used for ObjC.
@@ -61,11 +63,9 @@ public:
     unsigned ImplicitExternC : 1;
 
     Entry(StringRef path, frontend::IncludeDirGroup group,
-          bool isFramework, bool ignoreSysRoot, bool isInternal,
-          bool implicitExternC)
+          bool isFramework, bool ignoreSysRoot, bool isInternal)
       : Path(path), Group(group), IsFramework(isFramework),
-        IgnoreSysRoot(ignoreSysRoot), IsInternal(isInternal),
-        ImplicitExternC(implicitExternC) {}
+        IgnoreSysRoot(ignoreSysRoot), IsInternal(isInternal) {}
   };
 
   struct SystemHeaderPrefix {
@@ -126,10 +126,9 @@ public:
 
   /// AddPath - Add the \p Path path to the specified \p Group list.
   void AddPath(StringRef Path, frontend::IncludeDirGroup Group,
-               bool IsFramework, bool IgnoreSysRoot,
-               bool IsInternal = false, bool ImplicitExternC = false) {
+               bool IsFramework, bool IgnoreSysRoot, bool IsInternal = false) {
     UserEntries.push_back(Entry(Path, Group, IsFramework,
-                                IgnoreSysRoot, IsInternal, ImplicitExternC));
+                                IgnoreSysRoot, IsInternal));
   }
 
   /// AddSystemHeaderPrefix - Override whether \#include directives naming a