[Patch] clang-cl: add support for /? and /help

[Hans Wennborg]

On Tue, Jul 23, 2013 at 10:56 AM, Reid Kleckner <rnk at google.com> wrote:
> I think we want to have a whitelist of "clang options" that are distinct
> from gcc options, rather than blacklisting a troublesome few (-MD) as
> GCCOptions.  That seemed to be the main conclusion of the discussion on
> cfe-dev.

I thought for a while that blacklisting "a troublesome few" would make
for a much shorter list than whitelisting "clang options", but now
that I look at the file again, I see that there's a very large amount
of options that don't apply to clang-cl, and lots of conflicts too.

I've attached a new patch that does the whitelist approach, and starts
with a pretty short whitelist. I figure we can add more stuff too it
as needed.

> We obviously don't want to add Flags<[ClangOption]> to every option in
> f_Group and f_clang_Group, so there'll have to be some tablegen magic in
> there.

I'm not sure we want to whitelist everything in f_Group and
f_clang_Group, though. For example, -fapple-kext is in f_Group, which
doesn't make sense for clang-cl. In g_clang_Group we have the
sanitizer options, maybe we want to hold off exposing those options
until we support them? There's also -fno-inline, which maybe we don't
want to expose since clang-cl will have /Ob0?

Thanks,
Hans


> On Mon, Jul 22, 2013 at 8:38 PM, Hans Wennborg <hans at chromium.org> wrote:
>>
>> Hi all,
>>
>> The attached patch makes clang-cl handle the /? and /help command-line
>> flags.
>>
>> These are both just aliases to the regular -help flag, but this puts
>> the code in place for accepting (and printing as part of the help
>> message) different flags depending on the driver mode.
>>
>> Please take a look!
>>
>> Thanks,
>> Hans
-------------- next part --------------
A non-text attachment was scrubbed...
Name: first-cl-flags-2.diff
Type: application/octet-stream
Size: 19515 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20130723/bb5a834e/attachment.obj>