[Bug libstdc++/79017] Old PowerMac G5, MacPorts GCC 5.4, C++11 and "std::log2 has not been declared"

[noloader at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79017

--- Comment #15 from Jeffrey Walton <noloader at gmail dot com> ---
(In reply to Jonathan Wakely from comment #14)
> OK, thanks. I'm not going to try to add declarations like the libc++ patch
> does, as it looks like that would only be correct for Snow Leopard and not
> earlier.
> 
> I'll just add more fine-grained configure checks and if they're not declared
> in <math.h> then they won't be available, period. There's only so much we
> can do to work around buggy C libraries on the target.

Ack, thanks.

The MacPorts, Brew, Fink (etc) folks thank you.