LOG2_PLUS_EPSILON   38 maint/gnulib/lib/expl.c #define LOG2_PLUS_EPSILON 0.6931471805599454L
LOG2_PLUS_EPSILON   25 maint/gnulib/lib/expm1.c #define LOG2_PLUS_EPSILON 0.6931471805599454
LOG2_PLUS_EPSILON   35 maint/gnulib/lib/expm1l.c #define LOG2_PLUS_EPSILON 0.6931471805599454L