[llvm-strip] Allow only one input

[MaskRay]

Summary

Before, llvm-strip accepted a second argument but it would just be ignored.

[alexander-shaposhnikov]

Thanks!

[jhenderson]

Shouldn't this have a test?

[alexander-shaposhnikov]

James, as for me, I think (though, don't insist) we might add a test for
this but in this particular case it's not critical / long-term beneficial.
This is a temporary solution anyway. The thing is that llvm-strip doesn't
support multiple inputs while binutils strip does.
So as soon as we fix it (add proper support for multiple input files), the
test will be gone / replaced with a meaningful test for multiple files.

Kind regards,
Alexander Shaposhnikov

tools/llvm-objcopy/llvm-objcopy.cpp

 // exit.
 static CopyConfig parseStripOptions(ArrayRef<const char *> ArgsArr) {
   StripOptTable T;
   unsigned MissingArgumentIndex, MissingArgumentCount;
   llvm::opt::InputArgList InputArgs =
       T.ParseArgs(ArgsArr, MissingArgumentIndex, MissingArgumentCount);
 
   if (InputArgs.size() == 0) {
-    T.PrintHelp(errs(), "llvm-strip <input> [ <output> ]", "strip tool");
+    T.PrintHelp(errs(), "llvm-strip", "strip tool");
     exit(1);
   }
 
   if (InputArgs.hasArg(STRIP_help)) {
-    T.PrintHelp(outs(), "llvm-strip <input> [ <output> ]", "strip tool");
+    T.PrintHelp(outs(), "llvm-strip", "strip tool");
     exit(0);
   }
 
   SmallVector<const char *, 2> Positional;
   for (auto Arg : InputArgs.filtered(STRIP_UNKNOWN))
     error("unknown argument '" + Arg->getAsString(InputArgs) + "'");
   for (auto Arg : InputArgs.filtered(STRIP_INPUT))
     Positional.push_back(Arg->getValue());
 
   if (Positional.empty())
     error("No input file specified");
 
-  if (Positional.size() > 2)
+  if (Positional.size() > 1)
     error("Support for multiple input files is not implemented yet");
 
   CopyConfig Config;
   Config.InputFilename = Positional[0];
   Config.OutputFilename =
       InputArgs.getLastArgValue(STRIP_output, Positional[0]);
 
   Config.StripDebug = InputArgs.hasArg(STRIP_strip_debug);