[Bug fortran/81344] New: Can't disable -ffpe-trap (or not documented)

[jellby at yahoo dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81344

            Bug ID: 81344
           Summary: Can't disable -ffpe-trap (or not documented)
           Product: gcc
           Version: 5.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jellby at yahoo dot com
  Target Milestone: ---

Once I enable a floating point exception trap with "-ffpe-trap=whatever", it
doesn't seem to be possible to disable it in the same command line (as it is
possible with warnings, for instance. An empty list as in "-ffpe-trap=" is
accepted, but it doesn't disable traps.

This would be useful when using a tool like CMake, where it is convenient to
set a default set of flags, and then override them if desired in specific
files, rather.