David Schultz noticed that the FreeBSD libm does not set errno, never has done, and never will, and thus has made -fno-math-errno the default in the (old, GCC 4.2-based) system compiler:
http://svn.freebsd.org/viewvc/base?view=revision&revision=181538 We should also make this change for GCC 4.6 and possibly retroactively GCC 4.5 since we are giving away performance for nothing. Our documentation already notes that this is the case on Darwin On Darwin systems, the math library never sets @code{errno}. There is therefore no reason for the compiler to consider the possibility that it might, and @option{-fno-math-errno} is the default. which hacks config/i386/i386.c as follows: ix86_option_init_struct (struct gcc_options *opts) { if (TARGET_MACHO) /* The Darwin libraries never set errno, so we might as well avoid calling them when that's the only reason we would. */ opts->x_flag_errno_math = 0; I guess I could just add a check for FSB_MAJOR there, but that would only address i386. Is there a better way to accomplish this? Gerald
