Add libstdc++ search paths for GCC 4.6.0 on Arch Linux. Patch by Jakub Wieczorek.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130152 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/InitHeaderSearch.cpp b/lib/Frontend/InitHeaderSearch.cpp
index 6dbee9d..3da38fb 100644
--- a/lib/Frontend/InitHeaderSearch.cpp
+++ b/lib/Frontend/InitHeaderSearch.cpp
@@ -761,6 +761,13 @@
                                 "i686-pc-linux-gnu", "", "", triple);
     AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.3.1",
                                 "x86_64-unknown-linux-gnu", "", "", triple);
+
+    // Arch Linux gcc 4.6
+    AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.6.0",
+                                "i686-pc-linux-gnu", "", "", triple);
+    AddGnuCPlusPlusIncludePaths("/usr/include/c++/4.6.0",
+                                "x86_64-unknown-linux-gnu", "", "", triple);
+
     // Gentoo x86 gcc 4.5.2
     AddGnuCPlusPlusIncludePaths(
       "/usr/lib/gcc/i686-pc-linux-gnu/4.5.2/include/g++-v4",