Re: GCC optimizes integer overflow: bug or feature?

[Andrew Haley <aph at redhat dot com>]

Gabriel Dos Reis writes:
 > Andrew Haley <aph@redhat.com> writes:
 > 
 > | Robert Dewar writes:
 > |  > Andrew Haley wrote:
 > |  > 
 > |  > > We've already defined `-fwrapv' for people who need nonstandard
 > |  > > arithmetic.
 > |  > 
 > |  > Nonstandard implies that the result does not conform with the standard,
 > | 
 > | I don't think it does; it merely implies that any program which
 > | requires "-fwrapv" for correct execution is not a strictly conforming
 > | program.
 > 
 > How many useful C programs do you know that are strictly conforming?
 > Certainly, GCC isn't stritcly conforming.
 > 
 > I suspect the actual argument must be somewhere else.

I'm sure it is.  The only purpose of my mail was to clarify what I
meant by "nonstandard", which in this case was "not strictly
conforming".  I didn't intend to imply anything else.

In this case, there are two ways to view the program: either it has a
bug, or it has an environmental depencency on wrapping integer
arithmetic.

Andrew.