On 2011-05-16 02:15:57 +0200, Vincent Lefevre wrote: > -mabi=ieeelongdouble seems to be the solution: > > ay:~> gcc -dM -E -xc /dev/null -mabi=ieeelongdouble | grep LDBL > cc1: warning: Using IEEE extended precision long double > #define __LDBL_MAX__ 1.18973149535723176508575932662800702e+4932L > #define __LDBL_MAX_EXP__ 16384 > #define __LDBL_HAS_INFINITY__ 1 > #define __LDBL_MIN__ 3.36210314311209350626267781732175260e-4932L > #define __LDBL_HAS_QUIET_NAN__ 1 > #define __LDBL_HAS_DENORM__ 1 > #define __LDBL_EPSILON__ 1.92592994438723585305597794258492732e-34L > #define __LDBL_MANT_DIG__ 113 > #define __LDBL_MIN_EXP__ (-16381) > #define __LDBL_MAX_10_EXP__ 4932 > #define __LDBL_DENORM_MIN__ 6.47517511943802511092443895822764655e-4966L > #define __LDBL_MIN_10_EXP__ (-4931) > #define __LDBL_DIG__ 33 > > 113-bit precision, that's quadruple precision! Unfortunately it's not usable in practice, at least under Debian: at link time, I get errors like: undefined reference to `_q_add' -- Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / Arénaire project (LIP, ENS-Lyon)
