How should we handle libgfortran and libm dependencies in offloaded code?
As the linking requirements especially regarding libgfortran may be
different for each offloading target (shared and/or static libraries
supported, static linking enforced, libquadmath needed, and so on), I
think the specific configuration must happen inside the offloading
execution path (mkoffload). Thus, trying to do this inside the gfortran
front end, gcc/fortran/gfortranspec.c:lang_specific_driver etc., does not
appear to be doing it the right way; for offloaded code, we'll always be
using the lto1 front end instead of the gfortran one. Is a libgfortran
link spec like libgomp's, together with some flag (similar to
-fopenmp/-fopenacc being used with the libgomp link spec) the right thing
to do?