signbit          2619 maint/gnulib/lib/math.in.h #  undef signbit
signbit          2621 maint/gnulib/lib/math.in.h #  define signbit(x) \
signbit          2627 maint/gnulib/lib/math.in.h #  undef signbit
signbit          2665 maint/gnulib/lib/math.in.h #  define signbit(x) \
signbit          2679 maint/gnulib/lib/math.in.h #    define signbit rpl_signbit
signbit          2689 maint/gnulib/lib/math.in.h #  define signbit(x) _GL_WARN_REAL_FLOATING_IMPL (signbit, x)