This is the mail archive of the libstdc++@gcc.gnu.org mailing list for the libstdc++ project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: V3 PATCH: numeric_limits<> support, fix PR/3865


Gabriel Dos Reis wrote:-

> |  Are
> | they going to be enabled only for C++ so C doesn't have to carry the
> | baggage?
> 
> The __WCHAR_UNSIGNED__ sign is defined only in C++ as explained.
> However other information about type precision and floating point
> format as defined both in C and C++.  Why do you think they are
> unnecessary in C? For proper floating point support in C99 and C++
> (i.e. without mismatch), both languages library supports have to share
> the same information.

Does Glibc not get it right at present?

> | Signedness of wchar_t is easily tested with if () or #if, for example;
> | a macro is quite redundant.
> 
> wchar_t is a keyword in C++, how do you easily test its signness with
> if(0 or #if at compile-time and having that information in accordance
> with the compiler's own idea?

if (L'\0' - 1 < 0)
   wchar_t_is_signed;
else
   wchar_t_is_unsigned;

Similarly for #if.

Neil.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]