fortran .mod files

[FX Coudert]

> For instance, is it safe to assume that all *.mod files produced with,
> say, gfortran from GCC 4.2.1 will (assuming in all cases an identical
> set of compiler flags) be compatible with gfortran as shipped in GCC
> 4.2.2?

 From what I remember, we have never formalized this. The current  
consensus, as I understand it, is that while there is no guarantee on  
compatibility, modules files are actually compatible within releases  
of the same branch (4.2 is a branch, 4.3 will be another one), unless  
of course there is a bug nasty enough to mandate fixing (a regression  
wrt to a previous release) that crept into module format. I don't  
think such a thing has occured for 4.2, but others may be more  
affirmative than me on this point (Paul or Tobias ?).

Hope this helps,
FX