[Bug libstdc++/60637] --fast-math breaks std::signbit function

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60637

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Mon Jan 18 16:28:16 2016
New Revision: 232531

URL: https://gcc.gnu.org/viewcvs?rev=232531&root=gcc&view=rev
Log:
Fix C++98 std::signbit<long double>

        PR libstdc++/60637
        * include/c_global/cmath (signbit) [__cplusplus < 201103L]: Use
        __builtin_signbitf or __builtin_signbitl as appropriate.
        * testsuite/26_numerics/headers/cmath/60637.cc: New.

Added:
   
branches/gcc-4_9-branch/libstdc++-v3/testsuite/26_numerics/headers/cmath/60637.cc
Modified:
    branches/gcc-4_9-branch/libstdc++-v3/ChangeLog
    branches/gcc-4_9-branch/libstdc++-v3/include/c_global/cmath