[ClangImporter] Don't add clang path when creating from cc1 commands

When creating ClangImporter directly from cc1 args, there is no need for
clang path, and it might even be mistaken as an input path. Don't use
clang executable path in the arguments when creating from cc1 commands.

Author: cachemeifyoucan

lib/ClangImporter/ClangImporter.cpp

@@ -976,9 +976,10 @@ ClangImporter::getOrCreatePCH(const ClangImporterOptions &ImporterOptions,
 std::vector<std::string>
 ClangImporter::getClangArguments(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(ctx.ClangImporterOpts.clangPath);
+  // When creating from driver commands, clang expects this to be like an actual
+  // command line. So we need to pass in "clang" for argv[0]
+  if (!ctx.ClangImporterOpts.DirectClangCC1ModuleBuild)
+    invocationArgStrs.push_back(ctx.ClangImporterOpts.clangPath);
   if (ctx.ClangImporterOpts.ExtraArgsOnly) {
     invocationArgStrs.insert(invocationArgStrs.end(),
                              ctx.ClangImporterOpts.ExtraArgs.begin(),

test/ClangImporter/pcm-emit-direct-cc1-mode.swift

@@ -9,8 +9,8 @@
 // CHECK-DUMP:   Module map file: {{.*[/\\]}}Inputs{{/|\\}}custom-modules{{/|\\}}module.map
 
 // Verify that the clang command-line used is cc1
-// RUN: %FileCheck -check-prefix CHECK-CLANG %s < %t.diags.txt
-// CHECK-CLANG: '{{.*[/\\]}}clang'{{.*}}'-fmodules'
+// RUN: %FileCheck -check-prefix CHECK-CLANG -DTRIPLE=%target-triple %s < %t.diags.txt
+// CHECK-CLANG: '{{.*[/\\]}}module.map' '-o' '{{.*[/\\]}}script.pcm' '-fmodules' '-triple' '[[TRIPLE]]' '-x' 'objective-c'
 
 import script
 var _ : ScriptTy