[PATCH] Add a barrier in the double fma implementation

[Roland McGrath]

I try to avoid knowing anything about floating-point.  But it seems like
this would be an issue for applications too.  I wonder if fetestexcept et
al shouldn't have barriers themselves?  I guess the public calls are actual
functions, so they are all implicit barriers--but does that hold under
static linking plus massive link-time interprocedural optimization (which
could come along some day even if it's not all here yet).

Is there any use of the libc_fe* calls in which a barrier is *not*
appropriate?


Thanks,
Roland