On 22/02/2019 15:41, David Brown wrote:
On 22/02/2019 15:29, Jonny Grant wrote:Would be good for -Wundef to be on by default We see a few times code silently left out of a build unless we use -Wundef Example below, the bug is this file didn't have a #define PROJ_DEF 1 Jonny // gcc -Wall -Wextra -c pre.c #include <stdio.h> int main() { #if PROJ_DEF printf("hello\n"); #endif return 0; }I think far too much code relies on this sort of construct and would throw up warnings while otherwise passing -Wall cleanly. As far as I can see from the C standards, using "#if PROJ_DEF" without defining the macro "PROJ_DEF" is not allowed, but I could be wrong - and it certainly has been common usage even if the standards disallow it.
Perhaps just adding to -Wextra would make sense? Regards, Jonny
