http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45831
--- Comment #13 from Manuel López-Ibáñez <manu at gcc dot gnu.org> 2010-09-30 12:12:17 UTC --- (In reply to comment #10) > To get to know what a formula does, I usually compute some examples. When > doing > so, I was warned, but ignored them and that was stupid. > > There are however also warnings that are stupid. I now think of setting an > integer to -2147483648. 2147483648 is too large for an integer and it is good > that the compiler warns you. Unfortunately, the compiler ignores the context > of > 2147483648 and thus warns for -2147483648 as well. A similar argument applies > for setting an unsigned to a value in the range 2147483648 to 4294967295. > > On the other hand, setting an unsigned to a negative value does not give any > warning. Setting an unsigned to e.g. -1 is totally unnecessary, since you can > write ~0 instead, which is also preferable. See: http://gcc.gnu.org/wiki/NewWconversion#Frequently_Asked_Questions Please search also the C FAQs, your answers are there. We cannot change how C works, even if it seems counter-intuitive at first glance. If you find another specific problem, please open a new PR with a complete testcase and expected/obtained output.
