Add the /nologo flag to llvm-ml

[ayzhao]

Summary

This flag is present in MSVC's ml.exe to suppress copyright info output.
LLVM doesn't output copyright info, so this flag does nothing in
llvm-ml. We still add this flag though so that when llvm-ml is used as a
drop-in replacement for MSVC ml.exe, we don't get any extra warnings.
Furthermore, this behavior is also consistent with other llvm binaries
for Windows (e.g. clang-cl, llvm-mt, lld-link, etc.)

[epastor]

Thanks!

[hans]

llvm/test/tools/llvm-ml/basic.test

3

This test would still pass if llvm-ml printed something like "error: invalid option: '/nologo'". It's probably safest to check that "nologo" isn't mentioned in the output at all.

llvm/tools/llvm-ml/Opts.td

70

For clang-cl we don't include ignored options in the /help output at all. See the cl_ignored_group in clang/include/clang/Driver/Options.td and how "nologo" is handled there. Maybe llvm-ml should handle ignored options similarly?

[ayzhao]

Update test for nologo

[ayzhao]

llvm/tools/llvm-ml/Opts.td

70

I don't think there's a consistent approach here - both llvm-cvtres and llvm-mt have help text for this flag (and in fact, I copied this help text from llvm-mt).

[hans]

I added a nitpick, but it's also fine if you want to land this now and worry about that later (or not).

llvm/tools/llvm-ml/Opts.td

70

It's a nitpick obviously, but I don't think the current help message is good:

• It doesn't explain what the flag does: it assumes that the reader already knows what it's supposed to do (print the "copyright data"), and then explains that it won't do that
• "Included for parity" is redundant, since *all* flags are included for parity with the original tool.

A better help text would be something like "Don't print startup banner (default)" or something like that. But just having no help text would be just as good.

I didn't realize llvm-cvtres and llvm-mt have the same issue, but I didn't review that code :-)

[ayzhao]

Remove the HelpText

[ayzhao]

llvm/tools/llvm-ml/Opts.td

70

Ended up removing the HelpText.

llvm/test/tools/llvm-ml/basic.test

-# RUN: not llvm-ml %t.blah.asm /Fo /dev/null 2>&1 | FileCheck -DMSG=%errc_ENOENT --check-prefix=ENOENT %s
+# RUN: not llvm-ml %t.blah.asm /nologo /Fo /dev/null 2>&1 | FileCheck -DMSG=%errc_ENOENT --check-prefix=ENOENT %s
 
+# ENOENT-NOT: nologo
 # ENOENT: {{.*}}.blah.asm: [[MSG]]

llvm/tools/llvm-ml/Opts.td

 
 def help : MLFlag<"?">,
            HelpText<"Display available options">;
 def help_long : MLFlag<"help">, Alias<help>;
 def assemble_only : MLFlag<"c">, HelpText<"Assemble only; do not link">;
 def define : MLJoinedOrSeparate<"D">, MetaVarName<"<macro>=<value>">,
              HelpText<"Define <macro> to <value> (or blank if <value> "
                       "omitted)">;
+def no_logo : MLFlag<"nologo">, HelpText<"">;
 def output_file : MLJoinedOrSeparate<"Fo">, HelpText<"Names the output file">;
 def include_path : MLJoinedOrSeparate<"I">,
                    HelpText<"Sets path for include files">;
 def safeseh : MLFlag<"safeseh">,
               HelpText<"Mark resulting object files as either containing no "
                        "exception handlers or containing exception handlers "
                        "that are all declared with .SAFESEH. Only available in "
                        "32-bit.">;
 def assembly_file : MLJoinedOrSeparate<"Ta">,
                     HelpText<"Assemble source file with name not ending with "

 def linker_map_file : UnsupportedJoined<"Fm">, HelpText<"">;
 def fp_emulator_fixups : UnsupportedFlag<"FPi">, HelpText<"">;
 def source_browser_file : UnsupportedJoined<"Fr">, HelpText<"">;
 def extended_source_browser_file : UnsupportedJoined<"FR">, HelpText<"">;
 def pascal_conventions : UnsupportedFlag<"Gc">, HelpText<"">;
 def c_conventions : UnsupportedFlag<"Gd">, HelpText<"">;
 def stdcall_conventions : UnsupportedFlag<"GZ">, HelpText<"">;
 def extern_name_limit : UnsupportedSeparate<"H">, HelpText<"">;
-def nologo : UnsupportedFlag<"nologo">, HelpText<"">;
 def omf_object_file : UnsupportedFlag<"omf">, HelpText<"">;
 def full_listing : UnsupportedFlag<"Sa">, HelpText<"">;
 def first_pass_listing : UnsupportedFlag<"Sf">, HelpText<"">;
 def listing_width : UnsupportedSeparate<"SI">, HelpText<"">;
 def listing_without_symbols : UnsupportedFlag<"Sn">, HelpText<"">;
 def listing_page_length : UnsupportedSeparate<"Sp">, HelpText<"">;
 def listing_subtitle : UnsupportedSeparate<"Ss">, HelpText<"">;
 def listing_title : UnsupportedSeparate<"St">, HelpText<"">;
 def listing_false_conditionals : UnsupportedFlag<"Sx">, HelpText<"">;
 def extra_warnings : UnsupportedFlag<"w">, HelpText<"">;
 def warning_level : UnsupportedJoined<"W">, HelpText<"">;
 def line_number_info : UnsupportedFlag<"Zd">, HelpText<"">;
 def export_all_symbols : UnsupportedFlag<"Zf">, HelpText<"">;
 def codeview_info : UnsupportedFlag<"Zi">, HelpText<"">;
 def enable_m510_option : UnsupportedFlag<"Zm">, HelpText<"">;
 def structure_packing : UnsupportedJoined<"Zp">, HelpText<"">;