Re: CXXFLAGS and linking

[William S Fulton]

Alexandre Duret-Lutz wrote:
>  William> This doesn't seem correct as the C++ flags aren't
>  William> necessarily appropriate for linking. 
>
> The example you sent to Guido uses `AM_CXXFLAGS = -DSOMETHING'.
> I wouldn't expect this to cause any trouble during linking.  Does it?
> (If so you should probably change it to `AM_CPPFLAGS = -DSOMETHING'.)
>
> Am I missing something?
>
>  William> This isn't consistent with the per-program
>  William> xxxx_CXXFLAGS which do not get passed to the
>  William> linker. Is this all as intended?
>
> I agree this is a bug.  We should honor per-target compiler
> flags at link time for consistency.
Well I was mainly confused at the inconsistency. FWIW I am trying a sort 
of workaround for the lack of per file compiler flags by having separate 
CFLAGS and CXXFLAGS, so although CPPFLAGS might be more appropriate it 
doesn't help my workaround.

The GNU compiler doesn't mind the -D and -I being passed during the 
linking stage and the only other compiler I've tried is M$ VC++ which 
issued a warning. I know this compiler is completely non standard, but I 
wasn't sure whether this would cause a problem for the host of other 
compilers which our project will be compiled by, so I'm watching this 
discussion with interest. Should it be the case it would be handy to 
have a little explanation in the docs that the CXXFLAGS/CFLAGS are also 
used during linking. It currently says it is passed to the compiler (C++ 
Support section).

I'm intrigued by why the introduction of per-program flags result in the 
object file being called maude-sample.o and not sample.o (Program and 
Library Variables section). Perhaps some short insight could be 
documented for inquisitives like myself?

Cheers
William