Michal Brzozowski <rusolis@poczta.fm> writes:
My friend is trying to run my game on his Debian unstable box
without success. It compiles fine, but he gets an "Illegal
instruction" whenever the game tries to run functions that draw 3d
graphics. The library that I use for graphics and other things is
Allegro (http://alleg.sf.net). After hours of debugging we haven't
found any bugs in the source code, and we only found out that the
game crashes at the first try of drawing anything in 3d. This means
the functions "apply_matrix_f()", "clip3d_f()" and
"persp_project_f()" from Allegro. I wasn't able to reproduce the
bug on my machine (Debian stable), nor did I hear of anybody else
having this problem. I still don't know where exactly the bug lies
(my game, Allegro, gcc, ...), so I'm asking you guys for help.
Maybe you can at least tell me what might cause an "Illegal
instruction"?
Usually, either an indirect jump using a corrupted pointer; or a
binary compiled for a CPU that has more features than that running the
binary. Usually, you can find that out by running the program under
gdb and using "disas".