Hi there,
i tried to compile a simple "Hello World" with dev-cpp,
but i get the following errors:
[linker error] undefined reference to 'atexit'
[linker error] undefined reference to 'atexit'
[linker error] undefined reference to 'atexit'
[build error][projekt1.exe]Error1

#include <allegro.h>

int main(int argc, char **argv){
allegro_init();
allegro_message("Hello World!");
} END_OF_MAIN()

Sounds like a standard (defaultly linked) library is not being linked in. atexit() should certainly exist and be linked in with your project, it's a function in stdlib.h -- did you perhaps toy with the linker settings when you were telling to dev-cpp to link in allegro? If so, try undo-ing those changed.

I would be greatly surprised if kdevil's suggestion works, since atexit() is probably called by allegro regardless of whether an explicit call to allegro_exit is made. There is no reason I know of to explicitly call allegro_exit if you plan to use allegro for the duration of the program runtime; for an allegro game, certainly, the call is probably deadweight.

Guys keep in mind that allegro_init is a macro, as allegro_init is the old-Allegro 3.0 style function. The new function is install_allegro which is compatible with dynamic linking operating systems (such as Windows and Linux) as it contains a driver ID, errno pointer, and atexit pointer to register itself. So atexit is directly used by the allegro_init macro.