24.09.2014, 23:26, Tom Lane kirjoitti:
> Peter Eisentraut <peter_e@gmx.net> writes:
>> On 9/24/14 9:21 AM, Tom Lane wrote:
>>> Agreed, but what about non-GCC compilers?
>
>> Stick AC_PROG_CC_C99 into configure.in.
>
> I think that's a bad idea, unless you mean to do it only on Solaris.
> If we do that unconditionally, we will pretty much stop getting any
> warnings about C99-isms on modern platforms. I am not aware that
> there has been any agreement to move our portability goalposts up
> to C99.
We don't currently try to select a C89 mode in configure.in, we just use
the default mode which may be C89 or C99 or something in between.
GCC docs used to say that once C99 support is complete it'll switch
defaults from gnu90 to gnu99, now the latest docs say that the default
will change to gnu11 at some point
(https://gcc.gnu.org/onlinedocs/gcc/Standards.html). Solaris Studio
already defaults to C99 and it looks like the latest versions of MSVC
also support it.
I think we should just enable C99 mode when possible to use the
backwards compatible features of it (like isinf). If C89 support is
still needed we should set up a new buildfarm animal that really uses a
C89 mode compiler and makes sure it compiles without warnings.
/ Oskari