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

[Paul Eggert]

On 10/01/2012 03:20 PM, Adrian Bunk wrote:
> Not if they are set to default to C99 mode.

Ah.  True.  That may be a problem for future
versions of these two compilers, though it's
not a problem for current versions.

To some extent, when we're talking about future
software, we're at the mercy of the future --
we really can't predict for sure.  It'd be nice
to have a more-plausible prediction than we currently
have,  But I'm not sure this is a good idea:

for test in test1 test2 test3
    for opt in '' -std=gnu11 -qlanglvl=extc1x
        if (run(test,opt) == SUCCESS)
            return opt
return NOT_SUPPORTED

For one thing, it's an O(N**3) algorithm
whereas we currently have O(N**2).  For another,
the individual tests may yield results that are
even less nice than what we have now.