[Clang][Driver] Remove -M group options before generating crash diagnostics

[aganea]

Summary

When using -MF file.d on the command line, file.d would not be deleted after a compiler crash.

Previously, the code path below had no effect, because TCArgs was already created after the crash, thus changes to TranslatedArgs would have no effect.

This was covered by clang/test/Driver/output-file-cleanup.c, the test was succeeding by fluke because Driver::generateCompilationDiagnostics() would fail to launch the subsequent clang -E (see D74070 for a fix for this). So the test was only covering code in Driver.cpp, L1492 and L1496 (C.CleanupFileMap). After this patch, both cleanup and removal of -MF are exercised.

This patch is point 2. in D73742

[rupprecht]

FYI - reverted this too since I had conflicts when also reverting D74070.

[aganea]

Relanded as rG75f09b54429bee17a96e2ba7a2ac0f0a8a7f7e74

[hans]

In D74076#1863987, @aganea wrote:

Relanded as rG75f09b54429bee17a96e2ba7a2ac0f0a8a7f7e74

Pushed that to 10.x as 0e1c734fa5b88ec7efc2bcf8d45ed58f6ba48b91

clang/lib/Driver/Compilation.cpp

void Compilation::initCompilationForDiagnostics() {
 
   // Clear temporary/results file lists.
   TempFiles.clear();
   ResultFiles.clear();
   FailureResultFiles.clear();
 
   // Remove any user specified output.  Claim any unclaimed arguments, so as
   // to avoid emitting warnings about unused args.
-  OptSpecifier OutputOpts[] = { options::OPT_o, options::OPT_MD,
-                                options::OPT_MMD };
+  OptSpecifier OutputOpts[] = {
+      options::OPT_o,  options::OPT_MD, options::OPT_MMD, options::OPT_M,
+      options::OPT_MM, options::OPT_MF, options::OPT_MG,  options::OPT_MJ,
+      options::OPT_MQ, options::OPT_MT, options::OPT_MV};
   for (unsigned i = 0, e = llvm::array_lengthof(OutputOpts); i != e; ++i) {
     if (TranslatedArgs->hasArg(OutputOpts[i]))
       TranslatedArgs->eraseArg(OutputOpts[i]);
   }
   TranslatedArgs->ClaimAllArgs();
 
+  // Force re-creation of the toolchain Args, otherwise our modifications just
+  // above will have no effect.
+  for (auto Arg : TCArgs)
+    if (Arg.second != TranslatedArgs)
+      delete Arg.second;
+  TCArgs.clear();
+
   // Redirect stdout/stderr to /dev/null.
   Redirects = {None, {""}, {""}};
 
   // Temporary files added by diagnostics should be kept.
   ForceKeepTempFiles = true;
 }
 
 StringRef Compilation::getSysRoot() const {
   return getDriver().SysRoot;
 }
 
 void Compilation::Redirect(ArrayRef<Optional<StringRef>> Redirects) {
   this->Redirects = Redirects;
 }

clang/test/Driver/output-file-cleanup.c

 
-// Temporarily disable this test until the -MF flag is properly removed from the diagnostics generation.
-// XFAIL: *
-
 // RUN: rm -f "%t.d" "%t1.s" "%t2.s" "%t3.s" "%t4.s" "%t5.s"
 //
 // RUN: touch %t.s
 // RUN: not %clang -S -DCRASH -o %t.s -MMD -MF %t.d %s
 // RUN: test ! -f %t.s
 // RUN: test ! -f %t.d
 
 // RUN: touch %t.s