[Bug libfortran/66458] Loading libgfortran.so changes the FPU exception flags

[fxcoudert at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66458

Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2015-07-05
                 CC|                            |fxcoudert at gcc dot gnu.org
           Assignee|unassigned at gcc dot gnu.org      |fxcoudert at gcc dot gnu.org
   Target Milestone|---                         |6.0
     Ever confirmed|0                           |1

--- Comment #4 from Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> ---
(In reply to kargl from comment #3)
> You're loading a dynamic library that has a constructor that is
> executed to set up the library's internal state.  If you're loading
> libraries and you want a specific FPU state, then you'll need to 
> save and reset the state.

Yet, if not FPE-specific option was passed, there is no good reason for us to
mess with the FPU state.

Anyway, currently something's a bit suboptimal here. For example, if a program
is compiled with -ffpe-trap, we're gonna call set_fpu() twice: once from the
constructor, then again from the main program. That doesn't seem right.