Re: [avr-gcc-list] WinAVR - gcc 3.4.6 - AVR Studio - DuoCore PC - Stackpointer problem

[Joerg Wunsch]

Steffen Rose <address@hidden> wrote:

[-fstack-check]

>> This is a completely unsupported (and IMHO non-working)
>> feature for the AVR.

> Where I can find a list about supported and unsupported options?

AFAICT stack checking is about the only completely unsupported feature
by now.  I wish GCC's documentation had put more emphasis on the fact
that this feature is not supported on all target platforms.  Right
now, the only hint you can get is that part of the documentation:

``Note that this switch does not actually cause checking to be done;
the operating system must do that.  The switch causes generation of
code to ensure that the operating system sees the stack being
extended.''

Consequently, and target platform that does not run on top of an
operating system cannot use this feature.  The library required for
the checks cannot even be built on the AVR, and thus AVR-GCC has to be
configured with --disable-libssp.

-- 

J"org Wunsch                                           Unix support engineer
address@hidden        http://www.interface-systems.de/~j/