On Fri, 30 Jan 2004 23:03:49 +0100, Wolfgang Meyerle wrote: > Please try out the following code snipet (not very large if you leave > the commented lines away... > > You can compile it with gcc -g 3d.c -lm -lvga -o 3d > > If you try it out it produces a segmentation fault... (Why???) > If you declare the variable count a little bit further down it doesn't > produce the segmentation fault. After I used ddd to locate the failure > it told me that the variable count is overwritten with strange numbers > that are out of the program memmory. > > I'm using gcc 3.2.2 on slackware 9.0 > > Isn't that strange ??? > > If you have any Idea what's going on there please let me know ...<snip>... > struct point3d points[4]; ...<snip>... > points[4].x=-412; > points[4].y=-50; > points[4].z=0.8; You declare points to be an array of 4 point3d structs, but then you access element 4 (and elements 5, 6, and 7). So you're stomping all over memory past the end of the array. That's where your 'strange numbers' come from. So it's a program bug, not GCC. S> -- <<< Eagles may soar, but weasels don't get sucked into jet engines >>> 10:15pm up 50 days 4:43, 19 users, load average: 0.20, 0.12, 0.14 Registered Linux User #232457 | LFS ID 11703
