On macOS search for libc++ headers in command-line tools and Xcode (fix issue #247).clang_3.9clang_3.9

PR https://github.com/include-what-you-use/include-what-you-use/pull/360

1 files changed, 15 insertions, 0 deletions

diff --git a/iwyu_driver.cc b/iwyu_driver.cc
index eb877ab..0d7bb65 100644
--- a/iwyu_driver.cc
+++ b/iwyu_driver.cc
@@ -21,6 +21,7 @@
 
 #include "llvm/ADT/ArrayRef.h"  // IWYU pragma: keep
 #include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/Triple.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/FileSystem.h"
@@ -211,6 +212,20 @@ CompilerInstance* CreateCompilerInstance(int argc, const char **argv) {
                                      args_start, args_end, diagnostics);
   invocation->getFrontendOpts().DisableFree = false;
 
+  // Use libc++ headers bundled with Xcode.app on macOS.
+  llvm::Triple triple(invocation->getTargetOpts().Triple);
+  if (triple.isOSDarwin() && invocation->getHeaderSearchOpts().UseLibcxx) {
+    invocation->getHeaderSearchOpts().AddPath(
+        "/Library/Developer/CommandLineTools/usr/include/c++/v1/",
+        clang::frontend::CXXSystem,
+        /*IsFramework=*/false, /*IgnoreSysRoot=*/true);
+    invocation->getHeaderSearchOpts().AddPath(
+        "/Applications/Xcode.app/Contents/Developer/Toolchains/"
+        "XcodeDefault.xctoolchain/usr/include/c++/v1",
+        clang::frontend::CXXSystem,
+        /*IsFramework=*/false, /*IgnoreSysRoot=*/true);
+  }
+
   // Show the invocation, with -v.
   if (invocation->getHeaderSearchOpts().Verbose) {
     errs() << "clang invocation:\n";