back out r149504

Too many weird build failures.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149571 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index bb92fee..2087c6a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -234,7 +234,7 @@
   PATTERN "*.inc"
   )
 
-add_definitions( -D_GNU_SOURCE )
+add_definitions( -D_GNU_SOURCE -DHAVE_CLANG_CONFIG_H )
 
 # Clang version information
 set(CLANG_EXECUTABLE_VERSION
diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index 5248c2e..89e0600 100644
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -36,9 +36,12 @@
 #include "InputInfo.h"
 #include "ToolChains.h"
 
-#include <map>
+#ifdef HAVE_CLANG_CONFIG_H
+# include "clang/Config/config.h"
+#endif
+#include "llvm/Config/config.h"
 
-#include "clang/Config/config.h"
+#include <map>
 
 using namespace clang::driver;
 using namespace clang;
diff --git a/lib/Driver/ToolChains.cpp b/lib/Driver/ToolChains.cpp
index 0f00f0b..0c8d3dc 100644
--- a/lib/Driver/ToolChains.cpp
+++ b/lib/Driver/ToolChains.cpp
@@ -33,7 +33,11 @@
 
 #include <cstdlib> // ::getenv
 
-#include "clang/Config/config.h"
+#ifdef HAVE_CLANG_CONFIG_H
+# include "clang/Config/config.h"
+#endif
+
+#include "llvm/Config/config.h" // for CXX_INCLUDE_ROOT
 
 using namespace clang::driver;
 using namespace clang::driver::toolchains;
diff --git a/lib/Frontend/InitHeaderSearch.cpp b/lib/Frontend/InitHeaderSearch.cpp
index 2736fd8..ee75e69 100644
--- a/lib/Frontend/InitHeaderSearch.cpp
+++ b/lib/Frontend/InitHeaderSearch.cpp
@@ -26,8 +26,11 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Path.h"
 
-#include "clang/Config/config.h"
+#ifdef HAVE_CLANG_CONFIG_H
+# include "clang/Config/config.h"
+#endif
 
+#include "llvm/Config/config.h"
 using namespace clang;
 using namespace clang::frontend;