Re: Do C++ signed types have modulo semantics?

[Gabriel Dos Reis <gdr at integrable-solutions dot net>]

Mark Mitchell <mark@codesourcery.com> writes:

| Michael Veksler wrote:
| 
| >> Most programmers "know" that arithmetic is modulo wordsize.  And those few
| >>who know the right answer (only unsigned arithmetic is modulo) will
| >>from time to time slip up and omit the "unsigned" keyword in their
| >>declarations.
| 
| I agree.
| 
| Although the standard clearly makes signed overflow undefined, I think
| it would be better if GCC defined it to be modulo arithmetic.  The
| degree to which that would result in inferior code seems likely to be
| somewhat small, and the amount of user confusion we would eliminate,
| and the number of programs that would not break with GCC, even though
| they work with other compilers, seems likely to be high.

Amen.

-- Gaby