http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53673
Pawel Sikora <pluto at agmk dot net> changed:
What |Removed |Added
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CC| |pluto at agmk dot net
--- Comment #2 from Pawel Sikora <pluto at agmk dot net> 2012-06-14 20:06:15
UTC ---
(In reply to comment #0)
> Can we have a magic weak symbol output by G++ into compilands saying what -std
> setting was used? For example:
>
> No -std outputs __gplusplus_std_cpluscplus98
> -std=c++03 outputs __gplusplus_std_cplusplus03
> -std=gnu++03 outputs __gplusplus_std_gnu03
> -std=c++11 outputs __gplusplus_std_cplusplus11
> -std=gnu++11 outputs __gplusplus_std_gnu11
> ... and so on ...
>
> Why? Because right now it's too easy to accidentally link object files
> compiled
> with 98 with those compiled with 11 and not then know why things spontaneously
> fail:
>
> http://gcc.gnu.org/ml/gcc/2012-06/msg00201.html
> http://gcc.gnu.org/wiki/Cxx11AbiCompatibility
>
> If __gplusplus_std_cpluscplus98 and __gplusplus_std_cplusplus11 both turn up
> in
> a shared object or executable, then we know we have combined 98 and 11 built
> code. Indeed, a future ld could warn if this happens.
>
> Niall
you can use -frecord-gcc-switches to detect mixed objects in linked library.
