https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79017
--- Comment #5 from Jeffrey Walton <noloader at gmail dot com> --- (In reply to Jonathan Wakely from comment #2) > (In reply to Jeffrey Walton from comment #0) > ... ^ > > Because these six functions are missing we treat all C99 math functions as > missing. We could split the checks into two pieces, so we check for these > separately, which would allow the rest of the C99 math library to be > imported into namespace std. > > But OS X 10.5.8 is pretty old, and this might not be worth doing if it > doesn't affect current versions of OS x. The issue seems to affect Android as well: http://stackoverflow.com/q/22922961. I am not sure if its the exact same issue however. Splitting the checks may benefit more than an ancient PowerMac. For what its worth, I keep the antique hardware around for testing on the PowerPC, which is big-endian. Otherwise it would be retired.