Re: Debugging Firefox

[coypu%SDF.ORG@localhost]

In case I was not verbose enough
pkgsrc is stripping debug symbols.
disable this with INSTALL_UNSTRIPPED=yes,
or debug the binaries in your work directory.

On Wed, Mar 30, 2016 at 10:44:45PM +0300, Andreas Gustafsson wrote:
> Hi all,
> 
> I'm trying to run Firefox under gdb on NetBSD 7.0/amd64, but I'm not
> having much luck.
> 
> I found a set of instructions at
> 
>   https://wiki.netbsd.org/tutorials/pkgsrc/debugging_firefox/
> 
> but when I follow them, gdb behaves stranegly, like being unable to
> set a breakpoint in main(), and getting SIGTRAPs seemingly at random:
> 
>   $ /usr/pkgsrc/www/firefox/work/build/dist/bin $ ./run-mozilla.sh -g ./firefox
>   [...]
>   (gdb) break main
>   Breakpoint 1 at 0x11be0: file /usr/pkgsrc/www/firefox/work/firefox-45.0.1/browser/app/nsBrowserApp.cpp, line 287.
>   (gdb) run
>   Starting program: /usr/pkgsrc/www/firefox/work/build/dist/bin/firefox 
>   Error in re-setting breakpoint 1: Cannot access memory at address 0x11be0
>   Error in re-setting breakpoint 1: Cannot access memory at address 0x11be0
> 
>   Program received signal SIGTRAP, Trace/breakpoint trap.
>   0x00007f7ff683c3ea in ?? ()
>   (gdb) where
>   #0  0x00007f7ff683c3ea in ?? ()
>   #1  0x00007f7ff78070f7 in ?? ()
>   #2  0x0000000100000246 in ?? ()
>   #3  0x00007f7ff7b8c400 in ?? ()
>   #4  0x00007f7fdebfec70 in ?? ()
>   #5  0x00007f7fee031a32 in ?? ()
>   #6  0x00000001ffffffff in ?? ()
>   #7  0x00007f7ff7b4a400 in ?? ()
>   #8  0x0001000100000012 in ?? ()
>   #9  0x0000000000000000 in ?? ()
> 
> And if I try to attach gdb to a running Firefox process, gdb seems to
> think I'm trying to debug ld.elf_so:
> 
>   (gdb) attach 25976 
>   Attaching to program: /usr/pkg/bin/firefox, process 25976
>   Reading symbols from /usr/libexec/ld.elf_so...(no debugging symbols found)...done.
>   Loaded symbols for /usr/libexec/ld.elf_so
>   0x00007f7ff689f65a in .rtld_start () from /usr/libexec/ld.elf_so
>   (gdb) where 
>   #0  0x00007f7ff689f65a in .rtld_start () from /usr/libexec/ld.elf_so
>   #1  0x00007f7ff7808f2b in ?? ()
>   #2  0x00007f7fc76ffb60 in ?? ()
>   #3  0x00007f7fcd847a48 in ?? ()
>   #4  0x00007f7fc76ffb40 in ?? ()
>   #5  0x00007f7ff1d9a324 in ?? ()
>   #6  0x0000000200000000 in ?? ()
>   #7  0x00007f7ff5f8b4d8 in ?? ()
>   #8  0x00000000c76ffbf0 in ?? ()
>   #9  0x00007f7fcbd09360 in ?? ()
>   #10 0x00007f7fc76ffba0 in ?? ()
>   #11 0x00007f7fcc4bf7a0 in ?? ()
>   #12 0x00007f7ffffeb118 in ?? ()
>   #13 0x0000000000000000 in ?? ()
> 
> Any hints?
> -- 
> Andreas Gustafsson, gson%gson.org@localhost

--