[compiler-rt] r229392 - tsan: fix compiler warning

[Dmitry Vyukov]

Added -Wno-maybe-uninitialized to mingw gcc flags and reverted the =0:
http://llvm.org/viewvc/llvm-project?view=revision&revision=229657


On Wed, Feb 18, 2015 at 10:29 AM, David Blaikie <dblaikie at gmail.com> wrote:
> well the one you quoted in the commit message is actually a GCC (mingw) one,
> which I think we've tried to disable (should be disabled with
> -Wno-maybe-uninitialized). Clang has a better version
> -Wsometimes-uninitialized anyway.
>
> As for disabling MSVC warnings... I'm sure we have a few disabled *tries to
> find them* Nope, don't recall where they are.
>
> On Tue, Feb 17, 2015 at 11:20 PM, Dmitry Vyukov <dvyukov at google.com> wrote:
>>
>> On Wed, Feb 18, 2015 at 10:17 AM, David Blaikie <dblaikie at gmail.com>
>> wrote:
>> >
>> >
>> > On Tue, Feb 17, 2015 at 11:16 PM, Dmitry Vyukov <dvyukov at google.com>
>> > wrote:
>> >>
>> >> On Tue, Feb 17, 2015 at 9:57 PM, David Blaikie <dblaikie at gmail.com>
>> >> wrote:
>> >> >
>> >> >
>> >> > On Mon, Feb 16, 2015 at 5:53 AM, Dmitry Vyukov <dvyukov at google.com>
>> >> > wrote:
>> >> >>
>> >> >> Author: dvyukov
>> >> >> Date: Mon Feb 16 07:53:00 2015
>> >> >> New Revision: 229392
>> >> >>
>> >> >> URL: http://llvm.org/viewvc/llvm-project?rev=229392&view=rev
>> >> >> Log:
>> >> >> tsan: fix compiler warning
>> >> >>
>> >> >> mingw gcc complains:
>> >> >> warning: 'err' may be used uninitialized in this function
>> >> >> [-Wmaybe-uninitialized]
>> >> >>        Printf("Failed to read options from '%s': error %d\n", value,
>> >> >> err);
>> >> >
>> >> >
>> >> > Was the warning correct? Or could we be sure that ReadFileToBuffer
>> >> > would
>> >> > initialize 'err'?
>> >> >
>> >> > Generally we should try not to unnecessarily initialize variables
>> >> > just
>> >> > to
>> >> > satisfy warnings because it hurts sanitizers (though I suppose that
>> >> > argument
>> >> > doesn't apply to the sanitizer libraries themselves - it still seems
>> >> > like a
>> >> > good principle to apply)
>> >>
>> >> I guess it is as incorrect as most of C++ compiler warnings.
>> >>
>> >> This happened on windows, where you usually don't have a great choice
>> >> of host compilers. So I am not sure how else we can resolve it.
>> >
>> >
>> > We simply disable the warnings, don't have to switch host compilers - we
>> > have a bunch of MSVC warnings disabled in our build configs already, I
>> > believe.
>>
>>
>> MSVC has own set of weird warnings. But do you disable such
>> fundamental warnings as "potentially unint var"?
>
>