fix a bug introduced in my previous patch: moving clang headers to the
"after" group instead of the system group makes it so #include <limits.h>
picks up the *system* limits.h file before clang's.  This causes a failure
on linux and is definitely not what we want.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@65026 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/InitHeaderSearch.cpp b/lib/Driver/InitHeaderSearch.cpp
index 4b5275d..5b0b2c2 100644
--- a/lib/Driver/InitHeaderSearch.cpp
+++ b/lib/Driver/InitHeaderSearch.cpp
@@ -24,7 +24,7 @@
 
 void InitHeaderSearch::AddPath(const std::string &Path, IncludeDirGroup Group,
                                bool isCXXAware, bool isUserSupplied,
-                               bool isFramework) {
+                               bool isFramework, bool IgnoreSysRoot) {
   assert(!Path.empty() && "can't handle empty path here");
   FileManager &FM = Headers.getFileMgr();
   
@@ -32,7 +32,7 @@
   llvm::SmallString<256> MappedPath;
   
   // Handle isysroot.
-  if (Group == System) {
+  if (Group == System && !IgnoreSysRoot) {
     // FIXME: Portability.  This should be a sys::Path interface, this doesn't
     // handle things like C:\ right, nor win32 \\network\device\blah.
     if (isysroot.size() != 1 || isysroot[0] != '/') // Add isysroot if present.