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

[Adrian Bunk]

On Tue, Sep 25, 2012 at 01:58:29PM -0700, Paul Eggert wrote:
> Sorry, I don't see a bug there.  "gcc -std=gnu99"
> accepts ISO C11, in the sense that it passes all the
> C11 tests that we have, if your version of GCC is
> sufficiently new.  This is because the GCC supports
> these C11 features even when running in C99 mode.

The only compiler for which autoconf currently knows how to set it into 
C11 mode passes the test in C99 mode.

That sounds a bit odd to me.

> If there's some C11 feature that is missing,
> a feature that it's reasonable to expect from C11
> compilers, we could add that to the test, and this
> will cause 'configure' to say "no" rather than "yes".
> I did briefly try to think of such a feature but
> came up dry.

What about

#if !defined(__STDC_VERSION__) || (__STDC_VERSION__ < 201112L)
#error compiler is not in C11 mode
#endif


cu
Adrian

-- 

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       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed