my first suspicions when a debugger can't give a useful backtrace are stack 
corruption or a call down a bogus function pointer.

Unfortunately such problems can be a nightmare to debug, I have often resorted to 
debugging with printf statements in the past. Recently "reverse debugging" 
tools have appeared that in principle should be able to help with this sort of thing, but 
I haven't found any free ones for arm linux.

On 13/01/2020 11:36, David Bremner wrote:
Dear Arm experts;

Any help with

  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=948789

would be appreciated.

I can replicate the crash on harris, and

cd $HOME/racket-7.5+dfsg1/build  && \
gdb --args ./racketcgc -cu \
$HOME/racket-7.5+dfsg1/src/racket/src/compile-startup.rkt cstartup.inc \
cstartup.zo $HOME/racket-7.5+dfsg1/src/racket/src/startup.inc \
$HOME/racket-7.5+dfsg1/src/racket/src/schvers.h

should get you to the segfault in gdb. The backtrace doesn't make much
sense to me, lots of talk about

   <error reading variable: DWARF-2 expression error: Loop detected (257).>

It's entirely possible racket is doing something odd with signals; I
remember something like using SEGFAULTS in gc.

d


Reply via email to