Index: lib/Driver/ToolChains/Linux.cpp
===================================================================
--- lib/Driver/ToolChains/Linux.cpp
+++ lib/Driver/ToolChains/Linux.cpp
@@ -924,6 +924,9 @@
       // Freescale SDK C++ headers are directly in <sysroot>/usr/include/c++,
       // without a subdirectory corresponding to the gcc version.
       LibDir.str() + "/../include/c++",
+      // Cray's gcc installation puts headers under "g++" without a
+      // version suffix.
+      LibDir.str() + "/../include/g++",
   };
 
   for (const auto &IncludePath : LibStdCXXIncludePathCandidates) {