Re: [Valgrind-users] Question: bug in user code, valgrind or glibc?

[Floyd, P. <pj...@wa...>]

Hi Chiaki

Debugging redirection issues isn't normally too slow. Redirection is 
done when Valgrind loads the guest executable and libraries.

Run Valgrind with --trace-redir=yes and you should see Valgrind printing 
what it finds in

  * ld.so, the link loader
  * the client executable
  * the valgrind tool
  * the valgrind shared lib preloads (core and tool)
  * any client shared libraries

libc falls under the last category, though there are a small number of C 
functions in the link loader (memcpy, strcmp etc).

You should see things like

--830--      ld-linux-x86-64.so.2 strcmp                         RL-> 
(2016.0) 0x040343b0
--830--      libc.so* __strcmp_sse42                 RL-> (2016.0) 
0x04034370
--830--      libc.so* __strcmp_sse2                  RL-> (2016.0) 
0x04034330
--830--      libc.so* __GI_strcmp                    RL-> (2016.0) 
0x040342f0

If you don't see any symbols being redirected then you have a problem.


A+

Paul