Re: AC_PROG_CC_C99 and -std=c99

[Paul Eggert]

On 06/18/2012 08:22 AM, 'Chris Hall' wrote:
> if some interface is not supported
> by the standard, I don't want it... because if I use something outside
> the standard I cannot reasonably expect some other c99 compiler to
> support it.  Surely ?

That's the theory, but in practice it doesn't work well,
and it's quite the opposite of the Autoconf philosophy,
which is to let programs use extensions when available,
if they want to.

> if gnu99 is in practice a more widely followed
> standard than ISO C99

It could well be, but it's nicer (where it's easy) if your
code is portable to a wider variety of C compilers.  It's
just that compiling with gcc -std=c99 is not that useful as
a method of checking portability.