Debugging and profiling libtool binaries

libtool takes care of a lot of the details of building binaries and shared libraries for you, but one of the side effects of this is that until you install your binaries the binaries in your build directory are actually shell script wrappers. Running gdb or profiling tools on the shell script won’t work:

# gdb ./mybinary 
GNU gdb (GDB) Fedora 7.5.1-42.fc18
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
...
"/home/will/mybinary": not in executable format: File format not recognized
(gdb)

However, you can get libtool to help you:

# libtool --mode=execute gdb ./mybinary
GNU gdb (GDB) Fedora 7.5.1-42.fc18
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
...
Reading symbols from /home/will/.libs/lt-mybinary...done.
(gdb)

This trick will also work for other tools like gprof and perf.

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