clang-cl: Add /showFilenames option (PR31957)

Add a /showFilenames option for users who want clang to echo the
currently compiled filename. MSVC does this echoing by default, and it's
useful for showing progress in build systems that doesn't otherwise
provide any progress report, such as MSBuild.

Differential Revision: https://reviews.llvm.org/D52773

llvm-svn: 344234

2 files changed, 13 insertions, 0 deletions

diff --git a/clang/lib/Driver/Job.cpp b/clang/lib/Driver/Job.cpp
index bd1a9bd8e3e..114efe1998c 100644
--- a/clang/lib/Driver/Job.cpp
+++ b/clang/lib/Driver/Job.cpp
@@ -315,6 +315,12 @@ void Command::setEnvironment(llvm::ArrayRef<const char *> NewEnvironment) {
 
 int Command::Execute(ArrayRef<llvm::Optional<StringRef>> Redirects,
                      std::string *ErrMsg, bool *ExecutionFailed) const {
+  if (PrintInputFilenames) {
+    for (const char *Arg : InputFilenames)
+      llvm::outs() << llvm::sys::path::filename(Arg) << "\n";
+    llvm::outs().flush();
+  }
+
   SmallVector<const char*, 128> Argv;
 
   Optional<ArrayRef<StringRef>> Env;
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 127f8069622..4d2cb14a51b 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -5067,6 +5067,13 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     C.addCommand(llvm::make_unique<Command>(JA, *this, Exec, CmdArgs, Inputs));
   }
 
+  // Make the compile command echo its inputs for /showFilenames.
+  if (Output.getType() == types::TY_Object &&
+      Args.hasFlag(options::OPT__SLASH_showFilenames,
+                   options::OPT__SLASH_showFilenames_, false)) {
+    C.getJobs().getJobs().back()->setPrintInputFilenames(true);
+  }
+
   if (Arg *A = Args.getLastArg(options::OPT_pg))
     if (!shouldUseFramePointer(Args, Triple))
       D.Diag(diag::err_drv_argument_not_allowed_with) << "-fomit-frame-pointer"