diff options
Diffstat (limited to 'misc/efgcvt.c')
-rw-r--r-- | misc/efgcvt.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/misc/efgcvt.c b/misc/efgcvt.c index 9348914ff2..dc711c63dc 100644 --- a/misc/efgcvt.c +++ b/misc/efgcvt.c @@ -17,6 +17,7 @@ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ +#include <math.h> #include <stdio.h> #include <stdlib.h> #include <sys/param.h> @@ -29,8 +30,13 @@ # define FLOAT_FMT_FLAG /* Actually we have to write (DBL_DIG + log10 (DBL_MAX_10_EXP)) but we don't have log10 available in the preprocessor. */ -# define MAXDIG (DBL_DIG + 3) -# define NDIGIT_MAX DBL_DIG +# define MAXDIG (NDIGIT_MAX + 3) +# if DBL_MANT_DIG == 53 +# define NDIGIT_MAX 17 +# else +/* See IEEE 854 5.6, table 2 for this formula. */ +# define NDIGIT_MAX (lrint (ceil (M_LN2 / M_LN10 * DBL_MANT_DIG + 1.0))) +# endif #endif #define APPEND(a, b) APPEND2 (a, b) |