signed is undefined and has been since 1992 (in GCC)

[Gabriel Dos Reis]

Falk Hueffner <falk@debian.org> writes:

| Michael Veksler <VEKSLER@il.ibm.com> writes:
| 
| > So maybe introduce a -fsigned-wraps flag, that the user can use
| > to make 'int' wrap even in loops.
| 
| We have that already, it's called "-fwrapv".

In the case of C++, it leads to ODR violation because of the presence
of numeric_limits<T>::is_modulo -- assuming you make GCC's behaviour
consistent.  

-- Gaby