Ian Lance Taylor writes: > Andrew Haley <[EMAIL PROTECTED]> writes: > > > If we're going to guarantee this stuff for the future, we'll have > > to fix the bug, make sure it's doesn't destabilize the compiler > > and write some test cases. If we're really serious about it we > > should make it a documented extension to C. I'm not exactly > > opposed to that, but I do wonder if it's the best use of people's > > time. But this is free software, and people choose their own > > priorities. > > We're currently breaking an existing free software program which > formerly worked although it relied on undefined behaviour.
I would argue that it was already broken and just worked by accident, but I suppose that's a matter of taste. > Therefore, I think that changing this would not be a complete waste > of time. Obviously I would never ask anybody else to work on it. > > I personally don't agree that this needs to be a documented extension. > I'm simply going on a more general rule which I tried to state above: > I don't think we should insert a trap call for undefined code. This isn't as simple as saying "don't insert a trap." If we make a change for openssh to allow this undefined behaviour, then do we agree to keep it working or not? If we agree that we will, then we have to at least add some test cases and we have to add some internal documentation to gcc. If we don't agree to keep it working, then even if we fix it today it may well break in the future. I don't think we're doing the developers of openssh any favours by compiling such code. Quite the reverse, IMO. Andrew.
