Re: [gccsdk] Using GCC 10 to build python

I managed to make some progress over the weekend and I've got the python binary built with GCC 10 (natively).

One thing I have found is that closing a taskwindow that's running python takes the machine out. Quiting python first is okay, but if you don't it totally hangs.

Cheers

Chris

On 12/03/2022 10:48 Lee Noar <lee.noar@sky.com> wrote:

On 09/03/2022 14:31, Chris Johns wrote:

Hello

I'd like to see if Python 3.10 will build with GCC 10.

I suspect there are a few issues that might come into play here. One is

that I usually build native, so it might take a week to build (IIRC GCC

10 is very slow when building native). I could probably get it to

cross-compile on my unix box though.

Cross-compiling is the better option because you have the benefit of the

autobuilder to build the dependencies. After building GCC 10, adding

RO_USE_ARMEABIHF=yes

to your build-setvars ensures that most things are then built with GCC

10 (there may be some old packages that make assumptions about the

compiler in use, but I think those are rare).

The second is the various shared libs that python uses.Am I right in

thinking that I would need to get (or build) compatible versions of them

all to work with the output of gcc 10?

Yes, GCC 10 uses a different stack extension strategy than previous

versions. Instead of building stack checks into the code and adding

new chunks to extend the stack, GCC 10 uses a flat stack and allocates

new stack memory pages on the fly via an abort handler. This has the

benefit of an extra work register (i.e. R10) and a stack layout that

matches what ported code is expecting (e.g. JITs, exception handlers).

Is does, however, mean that GCC 4 code and GCC 10 code are not

compatible.

Lee.