Fwd: All mips BSPs cannot link psxfenv01

Fwd: All mips BSPs cannot link psxfenv01

[Joel Sherrill]

I'm forwarding a discussion between Sebastian Huber and myself. Looks like
the mips fenv.h support was broken recently.

Any ideas?

---------- Forwarded message ---------
From: Sebastian Huber <sebastian.huber@embedded-brains.de>
Date: Sat, Jan 15, 2022, 1:01 PM
Subject: Re: All mips BSPs cannot link psxfenv01
To: <joel@rtems.org>
Cc: RTEMS <devel@rtems.org>


On 14/01/2022 17:51, Joel Sherrill wrote:
>> Is this due to the recent Newlib build system changes?
> I guess so although I don't see anything obvious when I
> looked at the machine/configure.ac in both versions.
>
>   I confirmed jmr3904 could build all tests with this gcc/newlib:
>
> $ ~/rtems-work/tools/6/bin/mips-rtems6-gcc --version
> mips-rtems6-gcc (GCC) 10.3.1 20211214 (RTEMS 6, RSB
> bb9e049b103f3a47019a6cfad18e2b59c9e9ea97, Newlib eb03ac1)
>
> That should have been the immediately previous version.

It is probably this change:

commit 8fa73a9f8414a4926365324c2fe32a237c2eb91d
Author: Jeff Johnston <jjohnstn@redhat.com>
Date:   Mon Nov 29 17:33:52 2021 -0500

     Modifying patch from: marian.buschsieweke@ovgu.de

     The code accessing the floating point control/status register, namely

             #define __cfc1(__fcsr)  __asm __volatile("cfc1 %0, $31" :
"=r" (__fcsr)

     does not compile with mips16. This changed the makefile to pass
-mno-mips16 to avoid the following
     compiler error:

             mips-mti-elf fails with "Error: unrecognized opcode `cfc1
$3,$31'"

I have no time to dig into the Newlib build system.

-- 
embedded brains GmbH
Herr Sebastian HUBER
Dornierstr. 4
82178 Puchheim
Germany
email: sebastian.huber@embedded-brains.de
phone: +49-89-18 94 741 - 16
fax:   +49-89-18 94 741 - 08

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Registernummer: HRB 157899
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Unsere Datenschutzerklärung finden Sie hier:
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Re: All mips BSPs cannot link psxfenv01

[Mike Frysinger]

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On 15 Jan 2022 15:50, Joel Sherrill wrote:
> I'm forwarding a discussion between Sebastian Huber and myself. Looks like
> the mips fenv.h support was broken recently.
> 
> Any ideas?

i happened to notice the same weirdness when rewriting the autotools logic.
looks like it's due to this patch:
https://sourceware.org/pipermail/newlib/2021/018726.html

i cc-ed you on the thread with a possible fix if you want to give it a try.
-mike

> ---------- Forwarded message ---------
> From: Sebastian Huber <sebastian.huber@embedded-brains.de>
> Date: Sat, Jan 15, 2022, 1:01 PM
> Subject: Re: All mips BSPs cannot link psxfenv01
> To: <joel@rtems.org>
> Cc: RTEMS <devel@rtems.org>
> 
> 
> On 14/01/2022 17:51, Joel Sherrill wrote:
> >> Is this due to the recent Newlib build system changes?
> > I guess so although I don't see anything obvious when I
> > looked at the machine/configure.ac in both versions.
> >
> >   I confirmed jmr3904 could build all tests with this gcc/newlib:
> >
> > $ ~/rtems-work/tools/6/bin/mips-rtems6-gcc --version
> > mips-rtems6-gcc (GCC) 10.3.1 20211214 (RTEMS 6, RSB
> > bb9e049b103f3a47019a6cfad18e2b59c9e9ea97, Newlib eb03ac1)
> >
> > That should have been the immediately previous version.
> 
> It is probably this change:
> 
> commit 8fa73a9f8414a4926365324c2fe32a237c2eb91d
> Author: Jeff Johnston <jjohnstn@redhat.com>
> Date:   Mon Nov 29 17:33:52 2021 -0500
> 
>      Modifying patch from: marian.buschsieweke@ovgu.de
> 
>      The code accessing the floating point control/status register, namely
> 
>              #define __cfc1(__fcsr)  __asm __volatile("cfc1 %0, $31" :
> "=r" (__fcsr)
> 
>      does not compile with mips16. This changed the makefile to pass
> -mno-mips16 to avoid the following
>      compiler error:
> 
>              mips-mti-elf fails with "Error: unrecognized opcode `cfc1
> $3,$31'"
> 
> I have no time to dig into the Newlib build system.
> 
> -- 
> embedded brains GmbH
> Herr Sebastian HUBER
> Dornierstr. 4
> 82178 Puchheim
> Germany
> email: sebastian.huber@embedded-brains.de
> phone: +49-89-18 94 741 - 16
> fax:   +49-89-18 94 741 - 08
> 
> Registergericht: Amtsgericht München
> Registernummer: HRB 157899
> Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler
> Unsere Datenschutzerklärung finden Sie hier:
> https://embedded-brains.de/datenschutzerklaerung/

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Re: All mips BSPs cannot link psxfenv01

[Sebastian Huber]

On 07/02/2022 07:43, Mike Frysinger wrote:
> On 15 Jan 2022 15:50, Joel Sherrill wrote:
>> I'm forwarding a discussion between Sebastian Huber and myself. Looks like
>> the mips fenv.h support was broken recently.
>>
>> Any ideas?
> i happened to notice the same weirdness when rewriting the autotools logic.
> looks like it's due to this patch:
> https://sourceware.org/pipermail/newlib/2021/018726.html

Yes, this is also my guess.

> 
> i cc-ed you on the thread with a possible fix if you want to give it a try.

I checked the latest Newlib master and the fenv objects are still empty.

-- 
embedded brains GmbH
Herr Sebastian HUBER
Dornierstr. 4
82178 Puchheim
Germany
email: sebastian.huber@embedded-brains.de
phone: +49-89-18 94 741 - 16
fax:   +49-89-18 94 741 - 08

Registergericht: Amtsgericht München
Registernummer: HRB 157899
Vertretungsberechtigte Geschäftsführer: Peter Rasmussen, Thomas Dörfler
Unsere Datenschutzerklärung finden Sie hier:
https://embedded-brains.de/datenschutzerklaerung/