[Bug fortran/51727] Changing module files

["tobi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51727

--- Comment #19 from Tobias Schlüter <tobi at gcc dot gnu.org> 2012-10-13 08:31:39 UTC ---
Simon,
I don't think the 'integer's are functions of the pointers once you process the
symbols in a defined order.  The non-determinism was caused by traversing the
pointer_info tree based on the non-deterministic pointers.  With the patch, the
tree is copied to a map sorted by the integers.  In the first iteration of
write_symbol1 these are given by the traversal of the namespace, which is
deterministic.  Since we now process these symbols in a deterministic order,
the integers of the symbols added during each iteration are also deterministic.
 I might be missing something, of course.

Joost,
it wouldn't be much work to implement the same thing using GFC_BBT instead of a
std::map.  It would require a typedef and one would have to cleanup the tree
manually, but if fixing old versions of gcc is valuable, I can do it.  I might
have to do this anyway, as I don't know if gfortran maintainers like C++isms
(even though in this particular case it's probably non-controversial).