[avr-gcc-list] Re: Exception handling methods (was: Re: AVR-G++)

[Rolf Magnus]

On Monday 28 August 2006 19:30, Bernd Trog wrote:
> On Sun, 27 Aug 2006, Rolf Magnus wrote:
> > On Sunday 27 August 2006 14:37, Bernd Trog wrote:
> > > --- Rolf Magnus <address@hidden> wrote:
> > > > Well, this is with sjlj exception handling. I now managed to compile
> > > > it with the newer exception handling method, and (at least I think
> > > > that was
> > >
> > > Interesting. How do you switch between these two exception handling
> > > methods?
> >
> > It's a configure switch for building gcc and libstdc++. From configure
> > --help:
> >
> >   --enable-sjlj-exceptions
> >                           force use of builtin_setjmp for exceptions
> >                           [default=auto]
> >
> > I used that at the begining, because I couldn't get it to compile
> > otherwise.
>
> OK, does this mean that I have to disable the sjlj exceptions with
> --enable-sjlj-exceptions=no
> to get the newer, smaller exception handling method?

The default is auto. I thought it was the exception handling that was 
responsible for the size decrease. But this seems not to be the case.

> When I configure gcc-4.1.1 with this flag, make fails with:
> [...]
> gcc -c -g -O2 -DIN_GCC -DCROSS_COMPILE -W -Wall -Wwrite-strings
> -Wstrict-proto types -Wmissing-prototypes -pedantic -Wno-long-long
> -Wno-variadic-macros -Wold-sty le-definition -Wmissing-format-attribute
> -Wno-error -DHAVE_CONFIG_H -DGENERATOR_ FILE -I. -Ibuild
> -I/src/source/gcc-4.1.1/gcc -I/src/source/gcc-4.1.1/gcc/build
> -I/src/source/gcc-4.1.1/gcc/../include
> -I/src/source/gcc-4.1.1/gcc/../libcpp/include
> -o build/insn-conditions.o insn-conditions.c
> In file included from insn-conditions.c:45:
> /src/source/gcc-4.1.1/gcc/except.h:155:6: error: #error
> "EH_RETURN_DATA_REGNO required"
> [...]

It seems I never got the other exception code. I have no clue why the code 
size at one point suddenly dropped from 20k to 11k.