[Clang] Alternate fix for "expansion of response files in -Wp after integrated-cc1 change"

[aganea]

Summary

After rGb4a99a061f517e60985667e39519f60186cbb469, passing a response file such as -Wp,@a.rsp wasn't working anymore because .rsp expansion happens inside clang's main() function.

This patch adds response file expansion in ExecuteCC1Tool().

Just noticing along the way that explicit flags provided to`-Wp` are parsed in the driver, whereas flags provided in the response file are parsed in the -cc1 tool. Which means one can't use the same flags inside the response file, as opposed to being provided directly, ie. -Wp,-MT,FOO.d. Saying -Wp,a.rsp, where a.rsp contains -MT,Foo.d would not work.

[aganea]

Remove Reenter flag as requested by @hans here.

[hans]

Looks reasonable to me.

clang/test/Driver/Wp-args.c

27

Why inception? I feel like I'm missing something :)

[aganea]

clang/test/Driver/Wp-args.c

27

Could be anything else :) Because -rewrite-macros prints this .c with comments, and then FileCheck looks for that tag in stdout.

[hans]

clang/test/Driver/Wp-args.c

27

Ah, I see.

Do you think it would be possible to do something simpler, like just pass a -D flag and check that it gets set? That would be easier for future readers of the test to understand.

[aganea]

clang/test/Driver/Wp-args.c

27

Done in the commit.

[hans]

Cherry-picked to 10.x in 85ee70e86456e3bcb3c706c404db497c5a448602

clang/include/clang/Driver/Driver.h

public:
 
   /// Whether the driver is generating diagnostics for debugging purposes.
   unsigned CCGenDiagnostics : 1;
 
   /// Pointer to the ExecuteCC1Tool function, if available.
   /// When the clangDriver lib is used through clang.exe, this provides a
   /// shortcut for executing the -cc1 command-line directly, in the same
   /// process.
-  typedef int (*CC1ToolFunc)(ArrayRef<const char *> argv);
+  typedef int (*CC1ToolFunc)(SmallVectorImpl<const char *> &ArgV);
   CC1ToolFunc CC1Main = nullptr;
 
 private:
   /// Raw target triple.
   std::string TargetTriple;
 
   /// Name to use when invoking gcc/g++.
   std::string CCCGenericGCCName;

clang/test/Driver/Wp-args.c

 
 // RUN: %clang -target i386-pc-linux-gnu -### \
 // RUN:   -Wp,-MMD -fsyntax-only %s 2> %t
 // RUN: FileCheck -check-prefix MMD < %t %s
 
 // MMD: "-cc1"
 // MMD-NOT: -MMD
 // MMD: "-dependency-file" "Wp-args.d"
+
+// Ensure response files are properly expanded with -Wp
+// RUN: echo -DTEST > %t.rsp
+// RUN: %clang -Wp,@%t.rsp -E %s | FileCheck -check-prefix RSP %s
+
+#ifdef TEST
+void foo();
+#endif
+
+// RSP: foo()

clang/tools/driver/driver.cpp

static void getCLEnvVarOptions(std::string &EnvValue, llvm::StringSaver &Saver,
                                SmallVectorImpl<const char *> &Opts) {
   llvm::cl::TokenizeWindowsCommandLine(EnvValue, Saver, Opts);
   // The first instance of '#' should be replaced with '=' in each option.
   for (const char *Opt : Opts)
     if (char *NumberSignPtr = const_cast<char *>(::strchr(Opt, '#')))
       *NumberSignPtr = '=';
 }
 
-static int ExecuteCC1Tool(ArrayRef<const char *> argv);
-
 static void SetBackdoorDriverOutputsFromEnvVars(Driver &TheDriver) {
   // Handle CC_PRINT_OPTIONS and CC_PRINT_OPTIONS_FILE.
   TheDriver.CCPrintOptions = !!::getenv("CC_PRINT_OPTIONS");
   if (TheDriver.CCPrintOptions)
     TheDriver.CCPrintOptionsFilename = ::getenv("CC_PRINT_OPTIONS_FILE");
 
   // Handle CC_PRINT_HEADERS and CC_PRINT_HEADERS_FILE.
   TheDriver.CCPrintHeaders = !!::getenv("CC_PRINT_HEADERS");
static void SetInstallDir(SmallVectorImpl<const char *> &argv,
   if (CanonicalPrefixes)
     llvm::sys::fs::make_absolute(InstalledPath);
 
   StringRef InstalledPathParent(llvm::sys::path::parent_path(InstalledPath));
   if (llvm::sys::fs::exists(InstalledPathParent))
     TheDriver.setInstalledDir(InstalledPathParent);
 }
 
-static int ExecuteCC1Tool(ArrayRef<const char *> argv) {
+static int ExecuteCC1Tool(SmallVectorImpl<const char *> &ArgV) {
   // If we call the cc1 tool from the clangDriver library (through
   // Driver::CC1Main), we need to clean up the options usage count. The options
   // are currently global, and they might have been used previously by the
   // driver.
   llvm::cl::ResetAllOptionOccurrences();
-  StringRef Tool = argv[1];
-  void *GetExecutablePathVP = (void *)(intptr_t) GetExecutablePath;
+
+  llvm::BumpPtrAllocator A;
+  llvm::StringSaver Saver(A);
+  llvm::cl::ExpandResponseFiles(Saver, &llvm::cl::TokenizeGNUCommandLine, ArgV,
+                                /*MarkEOLs=*/false);
+  StringRef Tool = ArgV[1];
+  void *GetExecutablePathVP = (void *)(intptr_t)GetExecutablePath;
   if (Tool == "-cc1")
-    return cc1_main(argv.slice(2), argv[0], GetExecutablePathVP);
+    return cc1_main(makeArrayRef(ArgV).slice(2), ArgV[0], GetExecutablePathVP);
   if (Tool == "-cc1as")
-    return cc1as_main(argv.slice(2), argv[0], GetExecutablePathVP);
+    return cc1as_main(makeArrayRef(ArgV).slice(2), ArgV[0],
+                      GetExecutablePathVP);
   if (Tool == "-cc1gen-reproducer")
-    return cc1gen_reproducer_main(argv.slice(2), argv[0], GetExecutablePathVP);
-
+    return cc1gen_reproducer_main(makeArrayRef(ArgV).slice(2), ArgV[0],
+                                  GetExecutablePathVP);
   // Reject unknown tools.
   llvm::errs() << "error: unknown integrated tool '" << Tool << "'. "
                << "Valid tools include '-cc1' and '-cc1as'.\n";
   return 1;
 }
 
 int main(int argc_, const char **argv_) {
   noteBottomOfStack();