How to compile gcc with no optimization and "-gdwarf-2 -g3"

How to compile gcc with no optimization and "-gdwarf-2 -g3"

[Liu Haibin]

Hi,

I want to build the whole gcc with "-gdwarf-2 -g3" and without any
optimization, so that I can debug gcc and see all the macros. I'm not
familiar with configure and make, so I tried to change all the CFLAGS
and others flags to "-gdwarf-2 -g3" in all the related files
(configure, configure.in, Makefile, Makefile.in, and Makefile.tpl). I
even changed the src/gcc/configure, src/gcc/Makefile.in and other
files. Basically, as long as I see something like "-g -O2", I change
it to "-gdwarf-2 -g3". And I configure it with

# ./configure --with-dwarf2
# make

But when it's compiling, I still see the -O2 optimization. And I tried

# ./configure --with-dwarf2
# make CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
BOOT_CFLAGS='-gdwarf-2 -g3'

It's still the same. I can see the -O2 optimization. When I debug cc1,
I cannot see the macros. (I applied the patch to gdb so that it is
able to see macros)

How should I do to compile gcc with no optimization and "-gdwarf-2 -g3"?

Thanks.


Regards,
Timothy

RE: How to compile gcc with no optimization and "-gdwarf-2 -g3"

[Rupert Wood]

Timothy wrote:

> And I tried
> 
> # ./configure --with-dwarf2
> # make CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
> BOOT_CFLAGS='-gdwarf-2 -g3'

I haven't done this for a while but I used to pass all the flags to
configure too, i.e.

    # CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
      BOOT_CFLAGS='-gdwarf-2 -g3' ./configure --with-dwarf2
    # make CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
      BOOT_CFLAGS='-gdwarf-2 -g3'

or just export them in advance (shell-specific)

    export CFLAGS='-gdwarf-2 -g3'
    export LIBCFLAGS='-gdwarf-2 -g3'
    export BOOT_CFLAGS='-gdwarf-2 -g3'
    ./configure --with-dwarf2
    make

Note that BOOT_CFLAGS probably won't make any difference since you're not
using "make bootstrap". If you're not building with a similar version of GCC
then you might want to bootstrap the compiler instead, but it sounds like
you know what you're doing!

Rup.

Re: How to compile gcc with no optimization and "-gdwarf-2 -g3"

[Liu Haibin]

Yes. It worked. Thanks a lot.


Regards,
Timothy


On 6/17/05, Rupert Wood <me@rupey.net> wrote:
> Timothy wrote:
> 
> > And I tried
> >
> > # ./configure --with-dwarf2
> > # make CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
> > BOOT_CFLAGS='-gdwarf-2 -g3'
> 
> I haven't done this for a while but I used to pass all the flags to
> configure too, i.e.
> 
>     # CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
>       BOOT_CFLAGS='-gdwarf-2 -g3' ./configure --with-dwarf2
>     # make CFLAGS='-gdwarf-2 -g3' LIBCFLAGS='-gdwarf-2 -g3'
>       BOOT_CFLAGS='-gdwarf-2 -g3'
> 
> or just export them in advance (shell-specific)
> 
>     export CFLAGS='-gdwarf-2 -g3'
>     export LIBCFLAGS='-gdwarf-2 -g3'
>     export BOOT_CFLAGS='-gdwarf-2 -g3'
>     ./configure --with-dwarf2
>     make
> 
> Note that BOOT_CFLAGS probably won't make any difference since you're not
> using "make bootstrap". If you're not building with a similar version of GCC
> then you might want to bootstrap the compiler instead, but it sounds like
> you know what you're doing!
> 
> Rup.
> 
>