DBL_MANT_BIT       31 gnulib-tests/float+.h # define DBL_MANT_BIT DBL_MANT_DIG
DBL_MANT_BIT       35 gnulib-tests/float+.h # define DBL_MANT_BIT (DBL_MANT_DIG * 2)
DBL_MANT_BIT       39 gnulib-tests/float+.h # define DBL_MANT_BIT (DBL_MANT_DIG * 4)