[PATCH] [libFuzzer] Allow non-fuzzer args after "--"

[Justin Bogner via llvm-commits]

Kostya Serebryany <kcc at google.com> writes:
> thought a bit more...
> It's really hard for me to verify that this change won't break anything,
> so how about making this in some different way?
> e.g.
> ./fuzzer-binary -flag1=foo -flag2=bar -ignore-all-following-arguments=1
> llvm-arg1 llvm-arg2

I really can't see it breaking anything that works today - most argument
parsers that treat '--' specially probably have a hard time with the
fuzzer args anyway. That said, I'm fine with some other sigil (though
this suggestion seems a little long). How about -ignore-remaining-args=1 ?

> (And please do use phabricator :)

Sure. I really find phabricator painful to use for reviewing, but I
suppose you're reviewing this, not me :)

> On Wed, Jul 12, 2017 at 2:52 PM, Kostya Serebryany <kcc at google.com> wrote:
>
>> 1. phabricator maybe?
>> 2. need to think. This flag business is messy
>>
>> On Wed, Jul 12, 2017 at 2:41 PM, Justin Bogner <mail at justinbogner.com>
>> wrote:
>>
>>> With this change, libFuzzer will ignore any arguments after an empty
>>> double dash argument, but it will preserve these arguments at the end
>>> of the command line when launching subprocesses. Using this, its
>>> possible to handle positional and single-dash arguments to the program
>>> under test by discarding everything up to "--" in LLVMFuzzerInitialize.
>>>
>>> The motivation here is in trying to set up fuzzers that use the LLVM
>>> backend, for example so that we can pass "-global-isel" in an ISel
>>> fuzzer to test that instead of SelectionDAG.
>>>
>>> Ok to commit?
>>>
>>>
>>