Re: bug: "gcc -std=gnu99" passes AC_PROG_CC_C11

[Paul Eggert]

On 09/25/2012 05:04 PM, Adrian Bunk wrote:
> If a future gcc version
> ...
> supports C11 features in gnu11 mode it doesn't support in
> gnu99 mode (likely)

I don't see this as likely, as I don't see any such features on the
horizon.  (I am excluding gets, which we don't want to be encouraging anyway.)

> Currently gcc is the only compiler where autoconf knows how to put it 
> into C11 mode, and __STDC_VERSION__ is defined in gnu11 mode.

But gcc normally doesn't define __STDC_VERSION__.  Granted,
gcc --std=gnu11 does define it, but all in all __STDC_VERSION__
is a bit squirrelly and I'd rather not be using it as part of a test.