Regenerating libgfortran files

[François-Xavier Coudert]

Hi all,

First the good news: I have finished regtesting a patch to the
front-end to enable library calls for real(10), real(16) and
integer(16) kinds, and although I thought the front-end would a real
pain to patch, I found it rather easy and there's no regression.

Now, I need to add libgfortran support for these large kinds. I think
I can figure out how to modify the m4 code, but I don't know how to
regenerate the files after that. I read contradictory information
about this process, and whether it is supposed to work or not. Can
someone give me a quick overview of this (pointers to doc welcome).

FX