Re: [PATCH] Pass various runtime library flags to GCC

[Ralf Wildenhues]

Hello Charles,  Yaakov,

thanks for the patch.

* Charles Wilson wrote on Mon, Feb 22, 2010 at 03:39:05PM CET:
> Original post went astray somehow...
> 
> 2009-12-30  Yaakov Selkowitz  <...>
> 
>     Pass various runtime library flags to GCC.
>     * libltdl/config/ltmain.m4sh (func_mode_link): Pass the
>     -shared-libgcc and -static-lib* flags along to GCC.
> 
>  ltmain.m4sh |    5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> As reported here (read the whole thread):
> http://www.cygwin.com/ml/cygwin/2009-08/msg00243.html

I think I read the whole thread, and for me it is not clear whether we
can allow to pass through any of these flags.

We store things like -lgcc_s and -lgcc in $postdeps on some systems, so
just letting the flags through at libtool --mode=link time without
adaptation of configure time decisions doesn't look right.

The thread does not clarify whether this has been tested, on what
platform(s), and whether with or without these flags also in LDFLAGS at
configure time, and whether the installed GCC was new enough to have
libtool files installed for these libraries.

Thanks,
Ralf

> --- a/libltdl/config/ltmain.m4sh
> +++ b/libltdl/config/ltmain.m4sh
> @@ -4527,8 +4527,11 @@ func_mode_link ()
>        # -p, -pg, --coverage, -fprofile-* pass through profiling flag for GCC
>        # @file GCC response files
>        # -tp=* Portland pgcc target processor selection
> +      # -{shared,static}-libgcc, -static-{libgfortran|libstdc++}: force GCC
> +      # to link against specified runtime library.
>        -64|-mips[0-9]|-r[0-9][0-9]*|-xarch=*|-xtarget=*|+DA*|+DD*|-q*|-m*| \
> -      -t[45]*|-txscale*|-p|-pg|--coverage|-fprofile-*|-F*|@*|-tp=*)
> +      -t[45]*|-txscale*|-p|-pg|--coverage|-fprofile-*|-F*|@*|-tp=*| \
> +      -shared-libgcc|-static-libgcc|-static-libgfortran|-static-libstdc++)
>          func_quote_for_eval "$arg"
>       arg="$func_quote_for_eval_result"
>          func_append compile_command " $arg"