[Driver] Fix multiple bugs related to dependency file options: -M -MM -MD -MMD -MT -MQ

-M -o test.i => dependency file is test.d, not test.i
-MM -o test.i => dependency file is test.d, not test.i
-M -MMD => bogus warning -Wunused-command-line-argument
-M MT dummy => -w not rendered

llvm-svn: 371918

clang/lib/Driver/Driver.cpp

@@ -3450,8 +3450,10 @@ Action *Driver::ConstructPhaseAction(
     llvm_unreachable("link action invalid here.");
   case phases::Preprocess: {
     types::ID OutputTy;
-    // -{M, MM} alter the output type.
-    if (Args.hasArg(options::OPT_M, options::OPT_MM)) {
+    // -M and -MM specify the dependency file name by altering the output type,
+    // -if -MD and -MMD are not specified.
+    if (Args.hasArg(options::OPT_M, options::OPT_MM) &&
+        !Args.hasArg(options::OPT_MD, options::OPT_MMD)) {
       OutputTy = types::TY_Dependencies;
     } else {
       OutputTy = Input->getType();

clang/lib/Driver/ToolChains/Clang.cpp

@@ -1061,7 +1061,6 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
                                     ArgStringList &CmdArgs,
                                     const InputInfo &Output,
                                     const InputInfoList &Inputs) const {
-  Arg *A;
   const bool IsIAMCU = getToolChain().getTriple().isOSIAMCU();
 
   CheckPreprocessingOptions(D, Args);
@@ -1070,9 +1069,20 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
   Args.AddLastArg(CmdArgs, options::OPT_CC);
 
   // Handle dependency file generation.
-  if ((A = Args.getLastArg(options::OPT_M, options::OPT_MM)) ||
-      (A = Args.getLastArg(options::OPT_MD)) ||
-      (A = Args.getLastArg(options::OPT_MMD))) {
+  Arg *ArgM = Args.getLastArg(options::OPT_MM);
+  if (!ArgM)
+    ArgM = Args.getLastArg(options::OPT_M);
+  Arg *ArgMD = Args.getLastArg(options::OPT_MMD);
+  if (!ArgMD)
+    ArgMD = Args.getLastArg(options::OPT_MD);
+
+  // -M and -MM imply -w.
+  if (ArgM)
+    CmdArgs.push_back("-w");
+  else
+    ArgM = ArgMD;
+
+  if (ArgM) {
     // Determine the output location.
     const char *DepFile;
     if (Arg *MF = Args.getLastArg(options::OPT_MF)) {
@@ -1080,8 +1090,7 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
       C.addFailureResultFile(DepFile, &JA);
     } else if (Output.getType() == types::TY_Dependencies) {
       DepFile = Output.getFilename();
-    } else if (A->getOption().matches(options::OPT_M) ||
-               A->getOption().matches(options::OPT_MM)) {
+    } else if (!ArgMD) {
       DepFile = "-";
     } else {
       DepFile = getDependencyFileName(Args, Inputs);
@@ -1090,8 +1099,22 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("-dependency-file");
     CmdArgs.push_back(DepFile);
 
+    bool HasTarget = false;
+    for (const Arg *A : Args.filtered(options::OPT_MT, options::OPT_MQ)) {
+      HasTarget = true;
+      A->claim();
+      if (A->getOption().matches(options::OPT_MT)) {
+        A->render(Args, CmdArgs);
+      } else {
+        CmdArgs.push_back("-MT");
+        SmallString<128> Quoted;
+        QuoteTarget(A->getValue(), Quoted);
+        CmdArgs.push_back(Args.MakeArgString(Quoted));
+      }
+    }
+
     // Add a default target if one wasn't specified.
-    if (!Args.hasArg(options::OPT_MT) && !Args.hasArg(options::OPT_MQ)) {
+    if (!HasTarget) {
       const char *DepTarget;
 
       // If user provided -o, that is the dependency target, except
@@ -1108,17 +1131,14 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
         DepTarget = Args.MakeArgString(llvm::sys::path::filename(P));
       }
 
-      if (!A->getOption().matches(options::OPT_MD) && !A->getOption().matches(options::OPT_MMD)) {
-        CmdArgs.push_back("-w");
-      }
       CmdArgs.push_back("-MT");
       SmallString<128> Quoted;
       QuoteTarget(DepTarget, Quoted);
       CmdArgs.push_back(Args.MakeArgString(Quoted));
     }
 
-    if (A->getOption().matches(options::OPT_M) ||
-        A->getOption().matches(options::OPT_MD))
+    if (ArgM->getOption().matches(options::OPT_M) ||
+        ArgM->getOption().matches(options::OPT_MD))
       CmdArgs.push_back("-sys-header-deps");
     if ((isa<PrecompileJobAction>(JA) &&
          !Args.hasArg(options::OPT_fno_module_file_deps)) ||
@@ -1127,8 +1147,8 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
   }
 
   if (Args.hasArg(options::OPT_MG)) {
-    if (!A || A->getOption().matches(options::OPT_MD) ||
-        A->getOption().matches(options::OPT_MMD))
+    if (!ArgM || ArgM->getOption().matches(options::OPT_MD) ||
+        ArgM->getOption().matches(options::OPT_MMD))
       D.Diag(diag::err_drv_mg_requires_m_or_mm);
     CmdArgs.push_back("-MG");
   }
@@ -1136,22 +1156,6 @@ void Clang::AddPreprocessingOptions(Compilation &C, const JobAction &JA,
   Args.AddLastArg(CmdArgs, options::OPT_MP);
   Args.AddLastArg(CmdArgs, options::OPT_MV);
 
-  // Convert all -MQ <target> args to -MT <quoted target>
-  for (const Arg *A : Args.filtered(options::OPT_MT, options::OPT_MQ)) {
-    A->claim();
-
-    if (A->getOption().matches(options::OPT_MQ)) {
-      CmdArgs.push_back("-MT");
-      SmallString<128> Quoted;
-      QuoteTarget(A->getValue(), Quoted);
-      CmdArgs.push_back(Args.MakeArgString(Quoted));
-
-      // -MT flag - no change
-    } else {
-      A->render(Args, CmdArgs);
-    }
-  }
-
   // Add offload include arguments specific for CUDA.  This must happen before
   // we -I or -include anything else, because we must pick up the CUDA headers
   // from the particular CUDA installation, rather than from e.g.

clang/test/Driver/m-and-mm.c

@@ -1,16 +1,34 @@
-// RUN: %clang -M -MM %s 2>&1 | FileCheck /dev/null --implicit-check-not=warning
+// RUN: %clang -M %s 2>&1 | FileCheck %s --implicit-check-not=warning
+// RUN: %clang -MM %s 2>&1 | FileCheck %s --implicit-check-not=warning
+
+// CHECK: m-and-mm.o:
+// TEST-I: {{.*}}test.i:
+// TEST: {{.*}}test:
 
 // RUN: mkdir -p %t.dir
+
+/// if -MD and -MMD are not specified, -o specifies the dependency file name.
+// RUN: rm -f %t.dir/test.i
+// RUN: %clang -M %s -o %t.dir/test.i
+// RUN: FileCheck %s < %t.dir/test.i
+// RUN: rm -f %t.dir/test.i
+// RUN: %clang -MM %s -o %t.dir/test.i
+// RUN: FileCheck %s < %t.dir/test.i
+
 // RUN: rm -f %t.dir/test.d
 // RUN: %clang -fsyntax-only -MD %s -o %t.dir/test.i
-// RUN: test -f %t.dir/test.d
+// RUN: FileCheck --check-prefix=TEST-I %s < %t.dir/test.d
+
+// RUN: rm -f %t.dir/test.d
+// RUN: %clang -M -MD %s -o %t.dir/test.i
+// RUN: FileCheck --check-prefix=TEST-I %s < %t.dir/test.d
 
 /// If the output file name does not have a suffix, just append `.d`.
 // RUN: rm -f %t.dir/test.d
 // RUN: %clang -fsyntax-only -MD %s -o %t.dir/test
-// RUN: test -f %t.dir/test.d
+// RUN: FileCheck --check-prefix=TEST %s < %t.dir/test.d
 
-#warning "-M and -MM suppresses preprocessing, thus this warning shouldn't show up"
+#warning "-M and -MM suppresses warnings, thus this warning shouldn't show up"
 int main(void)
 {
     return 0;