[Bug fortran/25708] Module loading is not good at all

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25708

--- Comment #11 from Paul Thomas <pault at gcc dot gnu.org> 2011-04-04 11:49:52 UTC ---
(In reply to comment #10)
> I would like to promote this one.  I have run into an application that is
> taking about 2 to 3 minutes to compile while other compilers can do so in a
> matter of seconds.  The delta here is huge.
> 
> I would also like to take a crack at it. Paul any progress on your end?

Dear Jerry,

I have to confess that I have not thought about it for quite a while.

It strikes me that it would be useful to profile module reading to find out
what takes the time.  In the case of the original example, it is clear that
repeating the same use statement cannot help; however, that begs that question
why it is so slow for each time.  Is it the IO, the lexing, or.....?

An associated issue is the size of module files.  Clearly, where a module uses
another module, we could help by inserting use statements in the module file.

Cheers

Paul