How to use gdb with LD_PRELOAD
Posting because we ran into a case where set environment
didn't work:
From GDB documentation:
set exec-wrapper wrappershow exec-wrapperunset exec-wrapper
When ‘exec-wrapper’ is set, the specified wrapper is used to launch programs for debugging. gdb starts your program with a shell command of the form exec wrapper program. Quoting is added to program and its arguments, but not to wrapper, so you should add quotes if appropriate for your shell. The wrapper runs until it executes your program, and then gdb takes control.
You can use any program that eventually calls execve with its arguments as a wrapper. Several standard Unix utilities do this, e.g. env and nohup. Any Unix shell script ending with exec "$@" will also work.
For example, you can use env to pass an environment variable to the debugged program, without setting the variable in your shell's environment:
(gdb) set exec-wrapper env 'LD_PRELOAD=libtest.so' (gdb) run