fix autoconf build from r133710

Sorry! This commit worked in CMake, but
CXX_INCLUDE_ROOT is defined in a different
config.h for autoconf.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@133715 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 4cd96beb05e2de5bdc1df1227f05f8a7e2deedd9..5eb859446f71bdabad8bd1cf69d7440eb634e43a 100644 (file)
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -36,6 +36,8 @@
 
 #include <cstdlib> // ::getenv
 
+#include "llvm/Config/config.h" // for CXX_INCLUDE_ROOT
+
 using namespace clang::driver;
 using namespace clang::driver::toolchains;