Modifying GCC's default search dirs

[Shaun Jackman]

With a little experimentation, I found out the default search
directories of GCC.

Given the compile time options of, for example, PREFIX=/usr,
MACHINE=i486-linux-gnu, VERSION=4.0.1, and the default
GCC_EXEC_PREFIX=PREFIX/lib/gcc
... the default library search paths are...
	GEP/M/V
	GEP/M/V/../../../../M/lib/M/V
	GEP/M/V/../../../../M/lib
... and the default include search paths are...
	GEP/M/V/../../../../M/sys-include
	GEP/M/V/include
	GEP/M/V/../../../../M/include

Now one can change GEP by either setting the environment variable or
with the -B switch. However, what I'd really like to modify is the
entire GEP/M/V portion, as well as the M in
../../../../M/{include,lib}. Can this be done?

(as a little experiment, I copied the gcc binary, searched for the
string i486-linux-gnu, and hacked it with an editor to be something
else, and this did have the desired effect of changing the parameter M
above!)

Please cc me in your reply. Thanks again,
Shaun