Olivier Langlois writes: > Maybe it has something to do with my compilation switches [...] > -Wall -fno-common -fno-exceptions -O1 -fforce-mem [...] 'man gcc' tells us: -fno-common In C, allocate even uninitialized global variables in the data sec- tion of the object file, rather than generating them as common blocks. This has the effect that if the same variable is declared (without "extern") in two different compilations, you will get an error when you link them. The only reason this might be useful is if you wish to verify that the program will work on other systems which always work this way. That looks like your ``issue''...