Fix ar command line expansion on Windows.

[dmikulin]

Summary

On Windows expansion of regex file name patterns is the responsibility of each tool. Fix ar to do that.

[Bigcheese]

This is good, but this should be using llvm-ar's failIfError instead of adding ExitOnError. Moving the error handling to ExitOnError should be a separate commit if done.

Really all of our tools should be doing this, as it also (mostly) properly handles unicode paths on Windows.

[• espindola]

LGTM with the same request: Use failIfError.

llvm/trunk/test/tools/llvm-ar/regex-cmd.test

+RUN: yaml2obj %S/Inputs/elf.yaml -o %t.o
+
+RUN: rm -f %t.ar
+RUN: llvm-ar crs %t.ar %t.*
+RUN: llvm-ar tv %t.ar | FileCheck %s
+
+CHECK: regex-cmd.test{{.*}}.o

llvm/trunk/tools/llvm-ar/llvm-ar.cpp

 #include "llvm/Support/Errc.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/LineIterator.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/PrettyStackTrace.h"
+#include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Support/ToolOutputFile.h"
 #include "llvm/Support/raw_ostream.h"
 
 #if !defined(_MSC_VER) && !defined(__MINGW32__)
 #include <unistd.h>
 #else
int main(int argc, char **argv) {
   StringRef Stem = sys::path::stem(ToolName);
   if (Stem.find("dlltool") != StringRef::npos)
     return dlltoolDriverMain(makeArrayRef(argv, argc));
 
   if (Stem.find("ranlib") == StringRef::npos &&
       Stem.find("lib") != StringRef::npos)
     return libDriverMain(makeArrayRef(argv, argc));
 
-  for (int i = 1; i < argc; i++) {
+  SmallVector<const char *, 256> Argv;
+  SpecificBumpPtrAllocator<char> ArgAllocator;
+  failIfError(errorCodeToError(sys::Process::GetArgumentVector(
+      Argv, makeArrayRef(argv, argc), ArgAllocator)));
+
+  for (unsigned i = 1; i < Argv.size(); i++) {
     // If an argument starts with a dash and only contains chars
     // that belong to the options chars set, remove the dash.
     // We can't handle it after the command line options parsing
     // is done, since it will error out on an unrecognized string
     // starting with a dash.
     // Make sure this doesn't match the actual llvm-ar specific options
     // that start with a dash.
-    StringRef S = argv[i];
+    StringRef S = Argv[i];
     if (S.startswith("-") &&
         S.find_first_not_of(OptionChars, 1) == StringRef::npos) {
-      argv[i]++;
+      Argv[i]++;
       break;
     }
     if (S == "--")
       break;
   }
 
   // Have the command line options parsed and handle things
   // like --help and --version.
-  cl::ParseCommandLineOptions(argc, argv,
+  cl::ParseCommandLineOptions(Argv.size(), Argv.data(),
     "LLVM Archiver (llvm-ar)\n\n"
     "  This program archives bitcode files into single libraries\n"
   );
 
   if (Stem.find("ranlib") != StringRef::npos)
     return ranlib_main();
   if (Stem.find("ar") != StringRef::npos)
     return ar_main();
   fail("Not ranlib, ar, lib or dlltool!");
 }