------- Comment #27 from dave at hiauly1 dot hia dot nrc dot ca 2007-05-12
02:23 -------
Subject: Re: [4.3 Regression] FAIL:
27_io/basic_istream/extractors_arithmetic/char/12.cc execution test
> An additional remark on hppa: a *theoretical* possibility is that on hppa
> strtold (or sscanf), even if infinities are available, doesn't return an
> infinity in case of input overflow. As far as I know, that is strictly
> mandated
> only in C99. In that case, we could strengthen the check on
> __LDBL_HAS_INFINITY__ to one on _GLIBCXX_USE_C99, for example.
That's it. From the manpage:
If the correct value would cause overflow, positive _LDBL_MAX or
negative _LDBL_NMAX is returned (according to the sign of the value),
and errno is set to ERANGE. The __LDBL_MAX and __LDBL_NMAX macros are
provided to assist in checking the return values against _LDBL_MAX and
_LDBL_NMAX.
If the correct value would cause underflow, _ZERO is returned and
errno is set to ERANGE.
So, I guess we have to check errno.
Dave
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31836
