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Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex
From: |
Danny Milosavljevic |
Subject: |
Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello' |
Date: |
Fri, 8 Jan 2021 14:43:47 +0100 |
Hi Janneke,
On Fri, 08 Jan 2021 07:25:52 +0100
Jan Nieuwenhuizen <janneke@gnu.org> wrote:
> > Alignment could be disabled on the CPU
> >
> >
> > https://developer.arm.com/documentation/ddi0464/f/system-control/register-descriptions/system-control-register
> >
> > but I don't think EABI wants that.
>
> Hmm, what does this mean? We are not really using EABI, or are we?
VFP is a floating point unit on ARM CPUs. It has been designed to either
require aligned members and be fast, or not, depending on a CPU flag that
for example the kernel can set.
See also https://www.keil.com/support/man/docs/armcc/armcc_chr1359124231926.htm
for much more detail.
ARM is a famously mix-and-match CPU, so the client can choose whatever
they want.
If you choose aligned-only, you will get a bus error on misaligned access.
A single program really shouldn't be choosing--it's more the entire platform
doing the choosing.
EABI has standardized on particular settings, among which is required alignment.
<https://www.keil.com/support/man/docs/armcc/armcc_chr1359124228744.htm>
> So alignment should be fixed, but that's more work and you propose a
> workaround, right?
No, I wanted to find out what's going on first.
Now that grischka commented and I looked up the malloc docs, I suggest
to fix mes libc's malloc to align what it gives back. That's all--that
should fix everything.
We should provide maxalign_t to make it known to the user what the
malloc alignment we are using is.
pgprkX0ShOwJa.pgp
Description: OpenPGP digital signature
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', (continued)
Re: [bootstrappable] wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Paul Sherwood, 2021/01/06
- Re: [bootstrappable] wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Jan Nieuwenhuizen, 2021/01/07
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/07
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/07
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/07
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Jan Nieuwenhuizen, 2021/01/08
- Re: [Tinycc-devel] [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', arnold, 2021/01/08
- Re: [Tinycc-devel] [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Jan Nieuwenhuizen, 2021/01/08
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello',
Danny Milosavljevic <=
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/08
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Jan Nieuwenhuizen, 2021/01/08
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/08
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/08
- Re: [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Jan Nieuwenhuizen, 2021/01/08
Re: [Tinycc-devel] [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', grischka, 2021/01/08
Re: [Tinycc-devel] [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Danny Milosavljevic, 2021/01/08
RE: [bootstrappable] Re: [Tinycc-devel] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Orians, Jeremiah (DTMB), 2021/01/08
Re: [Tinycc-devel] [bootstrappable] Re: Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Vincent Lefevre, 2021/01/08
Re: [Tinycc-devel] [bootstrappable] Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello', Jan Nieuwenhuizen, 2021/01/08