How to debug shell cmds?

[Dusan Juhas]

Hello,
I'd like to force make utility to stop everytime
a shell command with a certain pattern is invoked
(for debug purpose).
Is it possible to do so without changing Makefile?

Eg: pattern is mkdir
Makefile:
...
$(PLATFORM)_obj/%.o:  %.c
        @echo "... $<"
        @mkdir $(PLATFORM)_obj > /dev/null 2>&1 || true
...

I'd like to stop on line @mkdir... to see what happend
and then restart 'make' exactly on this line.

Well, I know it's possible to compile 'make' with debug info
and run gdb, for instance. But is there a more convenient way?
-- 
Best regards,
Dusan Juhas