GDB debugging warnings

3
votes

When I try to debug my core-dump via gdb either in Qt or directly from terminal, it gives me bunches of warnings like below. Therefore my backtrace is not working properly.

warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.

warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available.

warning: Could not load shared library symbols for ). Do you need "set solib-search-path" or "set sysroot"?

Is this because my executable built without debugging symbols or is the problem about glibc? Do you have any solution to fix this?

1
qtgdblibc
It looks like gdb can't find the libraries mentioned. If they are shared libraries you might check to see if the search path is set in the environment so it can locate them. When you create a terminal session it might not inherit the same environment as run time. – Jay

1 Answers

9
votes

Is this because my executable built without debugging symbols or is the problem about glibc?

This has nothing to do with your executable.

GDB needs a version of libthread_db.so.1 that matches your libpthread.so.0, and is not finding such version.

Probable causes (from most to least probable):

  • You have stripped libpthread.so.0 (don't do that).
  • You've upgraded your glibc, but the upgrade was incomplete and did not update libthead_db.so.1
  • You are using some kind of cross-compilation environment, and really do need to set solib-search-path or set libthread-db-search-path such that GDB can find a matching libthread_db.so.1

You can see which versions of libthread_db GDB is trying with set debug libthread-db 1.