[Bug fortran/67541] -Wconversion-extra no warning on double = double + single

[jamiebayne at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67541

--- Comment #2 from Jamie Bayne <jamiebayne at hotmail dot com> ---
Ah, so it's fixed in trunk. Thanks for the info.

RE the warnings making sense: floating-point promotions may not lose data, but
they do have an associated runtime cost (about equivalent to an add on recent
Intel architectures), which can be important for code optimisation.