[Libunwind-devel] [patch] Fix for failing test-setjmp

[Paul Pluzhnikov]

On Mon, Nov 14, 2011 at 5:02 PM, Paul Pluzhnikov <address@hidden> wrote:

> P.S. test-setjmp is failing for me (before or after the patch).
> When I enable assertions (to confirm my new assertions are correct), I see:
>
>  lt-test-setjmp: ../../src/dwarf/Gparser.c:754: apply_reg_state: \
>    Assertion `rs->reg[17].where == DWARF_WHERE_EXPR' failed.
>
> which likely explains that failure.

The problem is actually two-fold:

First, the loops in {sig,}longjmp.c are "do { ... } while (unw_step() >= 0);"

But unw_step() returns 0 on reaching the end of the chain (_start),
and the loop should stop there.

The second problem is that with this commit:
  
http://repo.or.cz/w/glibc.git/commitdiff/c67da0b50e3d20f89d7bb352cd67dcf66d808e50
glibc obfuscates value of SP in jmp_buf, so we might as well just give up.

Patch attached.

Thanks,
-- 
Paul Pluzhnikov

libunwind-longjmp-20111114.txt
Description: Text document