[Bug 368292] [NEW] qprof sends wrong values to addr2line on amd64

[wdoekes]

Public bug reported:

Binary package hint: qprof

On my Ubuntu/Hardy-AMD64 on a Pentium D, qprof reports invalid values
that do not map to a real location.

Example:

walter at ananas:0:~/src/qprof-0.5.2$ /usr/bin/qprof ./tests/dumb_test
qprof: /home/walter/src/qprof-0.5.2/tests/dumb_test: 16 samples, 16 counts
[0x7fff3b347858]                                                 16	(100%)

That should be:

walter at ananas:0:~/src/qprof-0.5.2$ /usr/local/bin/qprof ./tests/dumb_test
qprof: /home/walter/src/qprof-0.5.2/tests/dumb_test: 16 samples, 16 counts
main                                                             16	(100%)


I've played around a bit with the sigcontext pointer, and it seems like I got it right by replacing (&si) with (scv + 40). I have too little knowledge of CPUs, ABI's and binary files in general to know why scv+40 is right, but in my preliminary tests, I got valuable output similar to that which I get on a i686 system (also Hardy).


Attached are:
qprof_bug_fix.patch - The one line patch that works for me
qprof_bug_cpuinfo.txt - cat /proc/cpuinfo
qprof_bug_gcc_dM_E.txt - gcc -dM -E - </dev/null


walter at ananas:0:~/src/qprof-0.5.2$ uname -a
Linux ananas.wjd.nu 2.6.24-23-generic #1 SMP Wed Apr 1 21:43:24 UTC 2009 x86_64 GNU/Linux
walter at ananas:0:~/src/qprof-0.5.2$ dpkg -l qprof | grep ii
ii  qprof                                  0.5.2-5                                              Profiling utilities for Linux


That's about all the information I can think of. Please let me know if there's anything I can assist with.


Greetings,
Walter Doekes

** Affects: qprof (Ubuntu)
     Importance: Undecided
         Status: New

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qprof sends wrong values to addr2line on amd64
https://bugs.launchpad.net/bugs/368292
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