[Bug regression/82626] New: -msse and -mfpmath=sse Causes __FLT_EVAL_METHOD__ to be -1

[gcc at grundis dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82626

            Bug ID: 82626
           Summary: -msse and -mfpmath=sse Causes __FLT_EVAL_METHOD__ to
                    be -1
           Product: gcc
           Version: 6.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: regression
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gcc at grundis dot de
  Target Milestone: ---

This was detected when compiling this:

echo "#include <cmath>" | g++ -x c++ - -msse -mfpmath=sse -o /dev/null

This combination of flags seems to cause a definition of __FLT_EVAL_METHOD__=-1
while it should be 2(?). This causes more issues later on code that relies on
that define. See https://sourceforge.net/p/mingw/bugs/2352/