Build compiler for maximum debugging (-g -O0)

[Brian Dessent]

Oliver Kellogg wrote:

> > If you wish to use non-default GCC flags when compiling the stage2 and
> > stage3 compilers, set BOOT_CFLAGS on the command line when doing
> > `make'.
> 
> Using bash as my shell, I tried like this:
> $ export BOOT_CFLAGS="-g"
> $ make

That's not what the above is telling you to do.  There's a difference
between setting a variable in the environment and overriding it on the
make command line.  In particular, settings in the environment do not
override variable assignments in the Makefile (unless you use -e), but
overrides on the make command invocation do.

> What is the correct way to get the installed compiler compiled with -g -O0
> for fullest possible debugging ?

I think you want

make BOOT_CFLAGS="-g"

Brian