Hi, please use gcc-help@ for this type of questions. On Tue, 29 Nov 2011, Nadezhda Ivanоvna Vyukova wrote: > I've explained the customer that by default char is treated > as signed char on our platform and therefore this program > does not conform ISO C90, as it causes the integer overflow > (undefined behavior). That is correct. > But he was not satisfied. > He argued that the program compiled with gcc-3.4.6 behaves > "correctly" and now the compiler silently produces an > incomprehensible code. There is no "correct" with undefined code. He simply was lucky with 3.4. > IMHO it would be better to issue a warning when a finite loop is > transformed to an infinite one (as a result of -ftree-vrp). -Wstrict-overflow gives a warning in this program. This warning isn't active by default. 4.1 didn't yet have this warning IIRC. Ciao, Michael.
