Re: question about linker

On 11/12/2024 12:57, bart wrote:

On 11/12/2024 09:18, Michael S wrote:

On Wed, 11 Dec 2024 05:37:15 -0000 (UTC)
antispam@fricas.org (Waldek Hebisch) wrote:

 

You are exagerating and that does not help communication.  In this
group there were at least one serious poster claiming to write code
depending only on features from older C standard.

>
For some definition of "serious".
>

People like this
presumably would care if some "toy" compiler discoverd non-compliance.
Concerning tcc, they have explicit endorsment from gawk developer:
he likes compile speed and says that gawk compiles fine using tcc.
>
In may coding I use gcc extentions when I feel that there is
substantial gain.  But for significant part of my code I prefer
to portablility, and that may include avoiding features not
supported by lesser compilers.  I the past tcc was not able
to compile code which I consider rather ordinary C, and due
to this and lack of support for my main target I did not use
tcc.  But tcc improved, ATM I do not know if it is good enough
for me, but it passed initial tests, so I have no reason to
disregard it.
>
BTW: IME "exotic" tools and targets help with finding bugs.
So even if you do not normally need to compile with some
compiler it makes sense to check if it works.
>

>
I would think that the main reason for David Brown's absence of
interest in tcc is simply because tcc do not have back ends for
targets that he cares about.
In particular, Arm port appears to be abandoned in 2003, so quite
likely tcc can't generate code that runs on MCUs with ARMv7-M
architecture that happens to be released first in the same year and
officially named in the 2004.

 I remember running TCC on both RPi1 (2012) and RPi4 (2019). That would be ARM32 (some version of ARMv7 I guess; I find ARM model numbers bewildering).
 It's possible I also tried TCC in the ARM64 mode of RPi4.
 So it sounds rather unlikely that TCC doesn't support ARM.
 

The difference between ARM core generations, architecture numbers, and other numberings is not at all easy to follow.  There are also different encodings available for the same instruction set, and of course many extensions (not quite as many as in the x86 world, but many).
Suffice it to say that as far as code generation is concerned, the Cortex-A devices on the RPi's are completely different from the Cortex-M devices in microcontrollers.  It's like comparing the 80286 with the Z80A.