failed to open `progs.src` for reading when in subdirectory

[hemebond]

I don't understand how to get gmqcc to use a progs.src file in a subdirectory.

$ gmqcc --help
usage: gmqcc [options] [files...]options:
  -s filename            add a progs.src file to be used

$ ls qc/progs.src
qc/progs.src

$ gmqcc -s qc/progs.src
failed to open `progs.src` for reading

$ gmqcc -s ./qc/progs.src
failed to open `progs.src` for reading

$ cd qc

$ gmqcc
Mode: progs.src
There are 43 items to compile:
...