Regarding this sometimes-add--latomic(-in-testsuite) that is revisited: When is it appropriate to make the user add -latomic to link their program? Perhaps different answers for fortran and C++. I'm guessing "always when using any atomic construct" for C.
I had a grep-look in gcc/doc before asking; I can't see we say anything. I don't think "when the target lacks certain atomic features" is a full valid answer, except pragmatically, to paper over a bug. brgds, H-P PS. I'll do the patch if you (someone) does the words.
