bruno> How could I know if -Werror is set?? Is there some macro set when it's bruno> used or not?? I want to 'force' the use of -Werror when compiling sources bruno> which include some headers. rkiesling> I had been planning such a feature in ctpp (shamless OT plug, I know), rkiesling> but there hasn't been any demand so far. I too would like this feature in GCC... along with an number of other warning flags ie: -Wmissing-prototypes, -Wstrict-prototypes etc.... I would like to do something like this: #if !defined(_GCC_Werror_defined) #error Project policy and procedure requires GNU GCC -Werror be enable. #endif -Duane.