Link tests after GCC_NO_EXECUTABLES

[Richard Sandiford]

Mark Mitchell <mark@codesourcery.com> writes:
> However, I think there's a solution.  In particular, on
> libstdc++-v3/configure.ac, we do:
>
> AC_LIBTOOL_DLOPEN
> AM_PROG_LIBTOOL
>
> The AC_LIBTOOL_DLOPEN call enables checking for dlopen support in
> libtool.  The libtool documentation says:
>
>      Enable checking for dlopen support. This macro should be used if
>      the package makes use of the `-dlopen' and `-dlpreopen' flags,
>      otherwise libtool will assume that the system does not support
>      dlopening.  The macro must be called *before* `AC_PROG_LIBTOOL'.
>
> But, for a bare-metal toolchain, I don't think we need that.  So, I'm
> guessing that:
>
>   if test "x${with_newlib}" != "xyes"; then
>     AC_LIBTOOL_DLOPEN
>   fi
>
> will fix the problem.  (We already have checks for $with_newlib
> elsewhere in configure.ac, so I think this is in the same spirit, though
> a libstdc++ maintainer would of course be best to review the patch.)
>
> Bernd, Richard, Rask, would one of you be willing to explore that route?

Sure, thanks for the suggestion.  I've built binutils with _start warning
turned into an error, so I'll see how far I get.

Richard