"Oliver Kowalke" <oliver.kowalke@xxxxxx> writes: > I get a segfault with following app - could you verify this? This program works fine for me (gcc 4.4.3, glibc 2.11.1, Ubuntu Lucid) in 64-bit mode. But now I see that you are using 32-bit mode. I can confirm that the program crashes for me in that mode. Looking at the 32-bit implementation of makecontext in glibc, I can see that the problem is that it doesn't set up correct unwind information for the parameters pushed on the stack. The effect is that the first parameter on the stack appears to be a PC value. I think this is a bug in glibc. It should be possible to arrange for unwind information which skips %ebx words on the stack. Ian
