Martin Jambor <[EMAIL PROTECTED]> writes: > I've been rebootstrapping my switch conversion patch (which is still > waiting for review) to make sure it still works. Unfortunately, it > did not. The error given was the following and I believe this is the > warning introduced by Ian as a response to the infamous CERT advisory. > (Furthermore, I am getting this warning at revision 134664 but I was > not getting it at 134135.) > > ------- Compiler output ------- > /cswtch/gcc/. -I/abuild/mjambor/cswtch/gcc/../include > -I/abuild/mjambor/cswtch/gcc/../libcpp/include > -I/abuild/mjambor/cswtch/gcc/../libdecnumber > -I/abuild/mjambor/cswtch/gcc/../libdecnumber/bid -I../libdecnumber > /abuild/mjambor/cswtch/gcc/tree-switch-conversion.c -o > tree-switch-conversion.o > cc1: warnings being treated as errors > /abuild/mjambor/cswtch/gcc/tree-switch-conversion.c: In function > 'process_switch': > /abuild/mjambor/cswtch/gcc/tree-switch-conversion.c:182: error: assuming > signed overflow does not occur when assuming that (X - c) > X is always false > make[3]: *** [tree-switch-conversion.o] Error 1 > ------------- End -------------
The warnings I added for the CERT advisory say "assuming pointer wraparound does not occur".... You are running into one of the older signed overflow warnings. > 1. Am I doing something wrong? No. > 2. How can I get rid of the error and bootstrap my code? Make branch_num an unsigned int. > 3. If the warning is really bogus, should we perhaps turn it off for > bootstrap, (or turn it off by default in general and leave it > there for people who want to check their code after reading CERT > advisories)? The basic criteria for -Wall is: could indicate a problem, easy to rewrite code to avoid. You've encountered a false positive, but it's easy to avoid. Ian
