Re: C99 compliance for src/port/snprintf.c

On 16/08/2018 14:30, Andres Freund wrote:
> Hi,
>
> On 2018-08-16 14:26:07 +0200, Peter Eisentraut wrote:
>> On 16/08/2018 13:18, Andres Freund wrote:
>>> checking for ccache gcc option to accept ISO C99... unsupported
>>>
>>> I suspect that's because of the '-ansi' flag in CFLAGS, not because
>>> the compiler is incapable of actually supporting C99.
>>
>> -ansi is equivalent to -std=c90. If we make the switch, the build farm
>> configuration should just probably replace -ansi with -std=c99.
>
> Right. I just hadn't checked the addition of -std=c99 doesn't override
> the -ansi. Presumably just an ordering thing.

The mistake is putting -ansi or similar options into CFLAGS. You need
to put them into CC.

The Autoconf test for C99 correctly puts the candidate options into CC,
but then if the test compilation invocation is something like "$CC
$CFLAGS -c conftest.c", the -ansi cancels out the earlier -std=c99 or
whatever.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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