On Sat, 1 Mar 2008, Richard Guenther wrote: > I seriously doubt anyone has used it for anything useful since at least > the advent of tree-ssa. I see we for example warn for -fforce-mem > in 4.2, but that is a no-op there. Do we have an option to disable > such warnings? After all it would break -Werror.
-fforce-mem isn't an option affecting the semantics of code the same way as -ftrapv is, and -ftrapv is more likely to be used manually from time to time to check for certain types of bugs rather than in makefiles with -Werror. Telling someone using it manually as a debugging tool that it's being deprecated seems useful. (NB: we should be clear that it's only the particular implementation that's proposed for deprecation and removal, and not the principle of having the -ftrapv feature should someone wish to fix or reimplement it.) Bruno Haible used -ftrapv to find bugs in GNU clisp a year ago <http://gcc.gnu.org/ml/gcc/2007-01/msg00294.html> (that message doesn't state whether the compiler version was post-tree-ssa). Building without optimization, as in that case, would I suppose have avoided some of the -ftrapv bugs. -- Joseph S. Myers [EMAIL PROTECTED]
