Am 30.03.2012 17:08, schrieb Ian Lance Taylor:
"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
I think the test app is not correct - on ppc32/linux it never returns.
Could you give me some hint how the stack unwind information is usally
writen on the stack/else where (some architectures do not save the
return address on the stack).
I believe the code is somewhere in the gcc sources - unfortunately I
don't know where (for what to grep for?)!
regards,
Oliver
