On 2018-08-18 08:01:46 +0200, Marc Glisse wrote: > I expect it is "bad" because it isn't clear if the value should be > sign-extended or zero-extended when cast to a larger integer. But that > doesn't really matter if you are only going to convert it back to a pointer, > where the extra bits will disappear. It isn't obvious that it warrants a > warning in -Wall (as opposed to -Wextra or something more specialized), but > if you are trying to use the extra high bits to stuff some extra > information, it may matter that they are not 0. But the C standard says that the behavior is undefined if the result cannot be represented in the integer type. Thus uintmax_t or intmax_t is safer than a integer type of the same size of the pointer, in case the pointer value as an integer would not be representable in this type, but would be in uintmax_t or intmax_t. So, IMHO, this warning is just bad. -- Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <https://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
