Fix include path detection on Fedora 15 with GCC 4.6.1.  Patch by Arthur Haas.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@141086 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/InitHeaderSearch.cpp b/lib/Frontend/InitHeaderSearch.cpp
index 4506774..16a905e 100644
--- a/lib/Frontend/InitHeaderSearch.cpp
+++ b/lib/Frontend/InitHeaderSearch.cpp
@@ -713,7 +713,12 @@
     //===------------------------------------------------------------------===//
     // Redhat based distros.
     //===------------------------------------------------------------------===//
-    // Fedora 15
+    // Fedora 15 (GCC 4.6.1)
+    AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.6.1",
+                                "x86_64-redhat-linux", "32", "", triple);
+    AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.6.1",
+                                "i686-redhat-linux", "", "", triple);
+    // Fedora 15 (GCC 4.6.0)
     AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.6.0",
                                 "x86_64-redhat-linux", "32", "", triple);
     AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.6.0",