diff options
Diffstat (limited to 'gl/intprops.h')
| -rw-r--r-- | gl/intprops.h | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/gl/intprops.h b/gl/intprops.h index 46f4d47d70..0c2787582f 100644 --- a/gl/intprops.h +++ b/gl/intprops.h @@ -68,13 +68,17 @@ # define signed_type_or_expr__(t) 1 # endif +/* Bound on length of the string representing an unsigned integer + value representable in B bits. log10 (2.0) < 146/485. The + smallest value of B where this bound is not tight is 2621. */ +# define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485) + /* Bound on length of the string representing an integer type or expression T. - Subtract 1 for the sign bit if T is signed; log10 (2.0) < 146/485; - add 1 for integer division truncation; add 1 more for a minus sign - if needed. */ + Subtract 1 for the sign bit if T is signed, and then add 1 more for + a minus sign if needed. */ # define INT_STRLEN_BOUND(t) \ - ((sizeof (t) * CHAR_BIT - signed_type_or_expr__ (t)) * 146 / 485 \ - + signed_type_or_expr__ (t) + 1) + (INT_BITS_STRLEN_BOUND (sizeof (t) * CHAR_BIT - signed_type_or_expr__ (t)) \ + + signed_type_or_expr__ (t)) /* Bound on buffer size needed to represent an integer type or expression T, including the terminating null. */ |