Pass in clang as arg[0] when invoking clang via the clang importer. Clang is expecting an argv[0] argument.

Author: gottesmm

lib/ClangImporter/ClangImporter.cpp

@@ -489,6 +489,10 @@ ClangImporter::create(ASTContext &ctx,
 
   std::vector<std::string> invocationArgStrs;
 
+  // Clang expects this to be like an actual command line. So we need to pass in
+  // "clang" for argv[0]
+  invocationArgStrs.push_back("clang");
+
   switch (importerOpts.Mode) {
   case ClangImporterOptions::Modes::Normal:
     getNormalInvocationArguments(invocationArgStrs, ctx, importerOpts);