"Marco Bodrato" <bodr...@mail.dm.unipi.it> writes: > ... if the compiler inlines the static gmp_tests_dbl_mant_bits function, > and optimizes away the local variable n, directly updating c in the loop, > then it can be a problem... suggestions? > We can declare c as int and n as unsigned. But I fear this is not a real > obstacle for an optimizer.
Might help to declare c and/or n as volatile. >> If we could use float.h constants, we wouldn't need to worry. > > In GMP we can #if HAVE_FLOAT_H ... but in mini-gmp? I think float.h is standard C (not sure which version, though). Configure check needed only for obscure systems. If it really is still needed for gmp, maybe we can have GMP define it, and let mini-gmp.c do something like #ifndef GMP_DOUBLE_MANTISA_DIGITS # include <float.h> # if FLT_RADIX == 2 # define GMP_DOUBLE_MANTISA_DIGITS DBL_MANT_DIG # endif #endif And later fall back to something generic and less precise if GMP_DOUBLE_MANTISA_DIGITS is not defined. I hope we don't need it though, since (i) it's a bit ugly, and (ii) gmp needs mini-gmp for the build system, not the host system, and I don't think we have any configure checks for float.h using CC_FOR_BUILD. I hope we can do the simple thing and include float.h unconditionally. Hmm, according to the ChangeLog, the configure test was added by Kevin Ryde in 2002, because the SunOS C compiler (the one bundled with the system if you didn't buy the SunPRO compiler separately, I guess) didn't provide it. Maybe it's time to delete that? Regards, /Niels -- Niels Möller. PGP-encrypted email is preferred. Keyid 368C6677. Internet email is subject to wholesale government surveillance. _______________________________________________ gmp-devel mailing list firstname.lastname@example.org https://gmplib.org/mailman/listinfo/gmp-devel