* [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu
@ 2026-05-17 4:14 Mingcong Bai
2026-05-17 13:54 ` David Laight
0 siblings, 1 reply; 6+ messages in thread
From: Mingcong Bai @ 2026-05-17 4:14 UTC (permalink / raw)
To: linux-kernel
Cc: Xi Ruoyao, Kexy Biscuit, Mingcong Bai, stable, kernel test robot,
Madhavan Srinivasan, Michael Ellerman, Nicholas Piggin,
Christophe Leroy (CS GROUP), linuxppc-dev
Similar to commit b929926f01f2 ("sh: define __BIG_ENDIAN for math-emu"),
define __LITTLE_ENDIAN and __BIG_ENDIAN as 0 to mitigate build-time
warnings:
./include/math-emu/double.h:59:21: error: ‘__BIG_ENDIAN’ is not defined, evaluates to ‘0’ [-Werror=undef]
59 | #if __BYTE_ORDER == __BIG_ENDIAN
|
Cc: stable@vger.kernel.org
Fixes: 13da9e200fe4 ("Revert "endian: #define __BYTE_ORDER"")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202507301656.7FEX6J5W-lkp@intel.com/
Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
---
arch/powerpc/include/asm/sfp-machine.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
index 8b957aabb826d..db8525605c026 100644
--- a/arch/powerpc/include/asm/sfp-machine.h
+++ b/arch/powerpc/include/asm/sfp-machine.h
@@ -319,10 +319,12 @@
#define abort() \
return 0
-#ifdef __BIG_ENDIAN
+#ifdef __BIG_ENDIAN__
#define __BYTE_ORDER __BIG_ENDIAN
+#define __LITTLE_ENDIAN 0
#else
#define __BYTE_ORDER __LITTLE_ENDIAN
+#define __BIG_ENDIAN 0
#endif
/* Exception flags. */
--
2.52.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu
2026-05-17 4:14 [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu Mingcong Bai
@ 2026-05-17 13:54 ` David Laight
2026-05-17 15:40 ` Xi Ruoyao
2026-05-20 13:14 ` Christophe Leroy (CS GROUP)
0 siblings, 2 replies; 6+ messages in thread
From: David Laight @ 2026-05-17 13:54 UTC (permalink / raw)
To: Mingcong Bai
Cc: linux-kernel, Xi Ruoyao, Kexy Biscuit, stable, kernel test robot,
Madhavan Srinivasan, Michael Ellerman, Nicholas Piggin,
Christophe Leroy (CS GROUP), linuxppc-dev
On Sun, 17 May 2026 12:14:21 +0800
Mingcong Bai <jeffbai@aosc.io> wrote:
> Similar to commit b929926f01f2 ("sh: define __BIG_ENDIAN for math-emu"),
> define __LITTLE_ENDIAN and __BIG_ENDIAN as 0 to mitigate build-time
> warnings:
>
> ./include/math-emu/double.h:59:21: error: ‘__BIG_ENDIAN’ is not defined, evaluates to ‘0’ [-Werror=undef]
> 59 | #if __BYTE_ORDER == __BIG_ENDIAN
> |
>
> Cc: stable@vger.kernel.org
> Fixes: 13da9e200fe4 ("Revert "endian: #define __BYTE_ORDER"")
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202507301656.7FEX6J5W-lkp@intel.com/
> Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
> ---
> arch/powerpc/include/asm/sfp-machine.h | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
> index 8b957aabb826d..db8525605c026 100644
> --- a/arch/powerpc/include/asm/sfp-machine.h
> +++ b/arch/powerpc/include/asm/sfp-machine.h
> @@ -319,10 +319,12 @@
> #define abort() \
> return 0
>
> -#ifdef __BIG_ENDIAN
> +#ifdef __BIG_ENDIAN__
> #define __BYTE_ORDER __BIG_ENDIAN
> +#define __LITTLE_ENDIAN 0
> #else
> #define __BYTE_ORDER __LITTLE_ENDIAN
> +#define __BIG_ENDIAN 0
> #endif
I thought the expected/correct value for __BYTE_ORDER__ was either 1234 or 4321.
(apart from pdp11's 2143).
-- David
>
> /* Exception flags. */
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu
2026-05-17 13:54 ` David Laight
@ 2026-05-17 15:40 ` Xi Ruoyao
2026-05-20 13:14 ` Christophe Leroy (CS GROUP)
1 sibling, 0 replies; 6+ messages in thread
From: Xi Ruoyao @ 2026-05-17 15:40 UTC (permalink / raw)
To: David Laight, Mingcong Bai
Cc: linux-kernel, Kexy Biscuit, stable, kernel test robot,
Madhavan Srinivasan, Michael Ellerman, Nicholas Piggin,
Christophe Leroy (CS GROUP), linuxppc-dev
On Sun, 2026-05-17 at 14:54 +0100, David Laight wrote:
> On Sun, 17 May 2026 12:14:21 +0800
> Mingcong Bai <jeffbai@aosc.io> wrote:
>
> > Similar to commit b929926f01f2 ("sh: define __BIG_ENDIAN for math-emu"),
> > define __LITTLE_ENDIAN and __BIG_ENDIAN as 0 to mitigate build-time
> > warnings:
> >
> > ./include/math-emu/double.h:59:21: error: ‘__BIG_ENDIAN’ is not defined, evaluates to ‘0’ [-Werror=undef]
> > 59 | #if __BYTE_ORDER == __BIG_ENDIAN
> > |
> >
> > Cc: stable@vger.kernel.org
> > Fixes: 13da9e200fe4 ("Revert "endian: #define __BYTE_ORDER"")
> > Reported-by: kernel test robot <lkp@intel.com>
> > Closes: https://lore.kernel.org/oe-kbuild-all/202507301656.7FEX6J5W-lkp@intel.com/
> > Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
> > ---
> > arch/powerpc/include/asm/sfp-machine.h | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
> > index 8b957aabb826d..db8525605c026 100644
> > --- a/arch/powerpc/include/asm/sfp-machine.h
> > +++ b/arch/powerpc/include/asm/sfp-machine.h
> > @@ -319,10 +319,12 @@
> > #define abort() \
> > return 0
> >
> > -#ifdef __BIG_ENDIAN
> > +#ifdef __BIG_ENDIAN__
> > #define __BYTE_ORDER __BIG_ENDIAN
> > +#define __LITTLE_ENDIAN 0
> > #else
> > #define __BYTE_ORDER __LITTLE_ENDIAN
> > +#define __BIG_ENDIAN 0
> > #endif
>
> I thought the expected/correct value for __BYTE_ORDER__ was either 1234 or 4321.
> (apart from pdp11's 2143).
Should we just do
#define __BYTE_ORDER __BYTE_ORDER__
#define __LITTLE_ENDIAN __ORDER_LITTLE_ENDIAN__
#define __BIG_ENDIAN __ORDER_BIG_ENDIAN__
then? __BYTE_ORDER__ etc. are available since gcc 4.6 and now we
requires gcc >= 8 to build the kernel.
--
Xi Ruoyao <xry111@xry111.site>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu
2026-05-17 13:54 ` David Laight
2026-05-17 15:40 ` Xi Ruoyao
@ 2026-05-20 13:14 ` Christophe Leroy (CS GROUP)
2026-05-20 18:43 ` David Laight
1 sibling, 1 reply; 6+ messages in thread
From: Christophe Leroy (CS GROUP) @ 2026-05-20 13:14 UTC (permalink / raw)
To: David Laight, Mingcong Bai
Cc: linux-kernel, Xi Ruoyao, Kexy Biscuit, stable, kernel test robot,
Madhavan Srinivasan, Michael Ellerman, Nicholas Piggin,
linuxppc-dev
Le 17/05/2026 à 15:54, David Laight a écrit :
> On Sun, 17 May 2026 12:14:21 +0800
> Mingcong Bai <jeffbai@aosc.io> wrote:
>
>> Similar to commit b929926f01f2 ("sh: define __BIG_ENDIAN for math-emu"),
>> define __LITTLE_ENDIAN and __BIG_ENDIAN as 0 to mitigate build-time
>> warnings:
>>
>> ./include/math-emu/double.h:59:21: error: ‘__BIG_ENDIAN’ is not defined, evaluates to ‘0’ [-Werror=undef]
>> 59 | #if __BYTE_ORDER == __BIG_ENDIAN
>> |
>>
>> Cc: stable@vger.kernel.org
>> Fixes: 13da9e200fe4 ("Revert "endian: #define __BYTE_ORDER"")
>> Reported-by: kernel test robot <lkp@intel.com>
>> Closes: https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Foe-kbuild-all%2F202507301656.7FEX6J5W-lkp%40intel.com%2F&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C08977974fb1c495e9bd508deb41bd275%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C639146228768693730%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=4qGulR%2BL7i7inksEbEH9jNGZS8HG80uvm3I9IyYzZww%3D&reserved=0
>> Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
>> ---
>> arch/powerpc/include/asm/sfp-machine.h | 4 +++-
>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
>> index 8b957aabb826d..db8525605c026 100644
>> --- a/arch/powerpc/include/asm/sfp-machine.h
>> +++ b/arch/powerpc/include/asm/sfp-machine.h
>> @@ -319,10 +319,12 @@
>> #define abort() \
>> return 0
>>
>> -#ifdef __BIG_ENDIAN
>> +#ifdef __BIG_ENDIAN__
>> #define __BYTE_ORDER __BIG_ENDIAN
>> +#define __LITTLE_ENDIAN 0
>> #else
>> #define __BYTE_ORDER __LITTLE_ENDIAN
>> +#define __BIG_ENDIAN 0
>> #endif
>
> I thought the expected/correct value for __BYTE_ORDER__ was either 1234 or 4321.
> (apart from pdp11's 2143).
That's the case, in include/linux/kconfig.h we have:
#ifdef CONFIG_CPU_BIG_ENDIAN
#define __BIG_ENDIAN 4321
#else
#define __LITTLE_ENDIAN 1234
#endif
But as far as I understand the problem is that math-emu expects
__BIG_ENDIAN to be defined at all time as it has tests like:
#if __BYTE_ORDER == __BIG_ENDIAN
Christophe
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu
2026-05-20 13:14 ` Christophe Leroy (CS GROUP)
@ 2026-05-20 18:43 ` David Laight
2026-05-20 22:05 ` Christophe Leroy (CS GROUP)
0 siblings, 1 reply; 6+ messages in thread
From: David Laight @ 2026-05-20 18:43 UTC (permalink / raw)
To: Christophe Leroy (CS GROUP)
Cc: Mingcong Bai, linux-kernel, Xi Ruoyao, Kexy Biscuit, stable,
kernel test robot, Madhavan Srinivasan, Michael Ellerman,
Nicholas Piggin, linuxppc-dev
On Wed, 20 May 2026 15:14:40 +0200
"Christophe Leroy (CS GROUP)" <chleroy@kernel.org> wrote:
> Le 17/05/2026 à 15:54, David Laight a écrit :
> > On Sun, 17 May 2026 12:14:21 +0800
> > Mingcong Bai <jeffbai@aosc.io> wrote:
> >
> >> Similar to commit b929926f01f2 ("sh: define __BIG_ENDIAN for math-emu"),
> >> define __LITTLE_ENDIAN and __BIG_ENDIAN as 0 to mitigate build-time
> >> warnings:
> >>
> >> ./include/math-emu/double.h:59:21: error: ‘__BIG_ENDIAN’ is not defined, evaluates to ‘0’ [-Werror=undef]
> >> 59 | #if __BYTE_ORDER == __BIG_ENDIAN
> >> |
> >>
> >> Cc: stable@vger.kernel.org
> >> Fixes: 13da9e200fe4 ("Revert "endian: #define __BYTE_ORDER"")
> >> Reported-by: kernel test robot <lkp@intel.com>
> >> Closes: https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Foe-kbuild-all%2F202507301656.7FEX6J5W-lkp%40intel.com%2F&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C08977974fb1c495e9bd508deb41bd275%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C639146228768693730%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=4qGulR%2BL7i7inksEbEH9jNGZS8HG80uvm3I9IyYzZww%3D&reserved=0
> >> Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
> >> ---
> >> arch/powerpc/include/asm/sfp-machine.h | 4 +++-
> >> 1 file changed, 3 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
> >> index 8b957aabb826d..db8525605c026 100644
> >> --- a/arch/powerpc/include/asm/sfp-machine.h
> >> +++ b/arch/powerpc/include/asm/sfp-machine.h
> >> @@ -319,10 +319,12 @@
> >> #define abort() \
> >> return 0
> >>
> >> -#ifdef __BIG_ENDIAN
> >> +#ifdef __BIG_ENDIAN__
> >> #define __BYTE_ORDER __BIG_ENDIAN
> >> +#define __LITTLE_ENDIAN 0
> >> #else
> >> #define __BYTE_ORDER __LITTLE_ENDIAN
> >> +#define __BIG_ENDIAN 0
> >> #endif
> >
> > I thought the expected/correct value for __BYTE_ORDER__ was either 1234 or 4321.
> > (apart from pdp11's 2143).
>
> That's the case, in include/linux/kconfig.h we have:
>
> #ifdef CONFIG_CPU_BIG_ENDIAN
> #define __BIG_ENDIAN 4321
> #else
> #define __LITTLE_ENDIAN 1234
> #endif
>
> But as far as I understand the problem is that math-emu expects
> __BIG_ENDIAN to be defined at all time as it has tests like:
>
> #if __BYTE_ORDER == __BIG_ENDIAN
The gcc docs have (https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html):
__BYTE_ORDER__
__ORDER_LITTLE_ENDIAN__
__ORDER_BIG_ENDIAN__
__ORDER_PDP_ENDIAN__
__BYTE_ORDER__ is defined to one of the values __ORDER_LITTLE_ENDIAN__, __ORDER_BIG_ENDIAN__, or __ORDER_PDP_ENDIAN__ to reflect the layout of multi-byte and multi-word quantities in memory. If __BYTE_ORDER__ is equal to __ORDER_LITTLE_ENDIAN__ or __ORDER_BIG_ENDIAN__, then multi-byte and multi-word quantities are laid out identically: the byte (word) at the lowest address is the least significant or most significant byte (word) of the quantity, respectively. If __BYTE_ORDER__ is equal to __ORDER_PDP_ENDIAN__, then bytes in 16-bit words are laid out in a little-endian fashion, whereas the 16-bit subwords of a 32-bit quantity are laid out in big-endian fashion.
You should use these macros for testing like this:
/* Test for a little-endian machine */
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
The doc doesn't mention the value, but __ORDER_BIG_ENDIAN__ is 4321 (decimal).
So the math-emu code is neither following gcc's rules or the kernel ones.
Your change will break anything that currently does:
#ifdef __BIG_ENDIAN
Any change would have to be limited to code that is implementing math-emu.
-- David
>
> Christophe
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu
2026-05-20 18:43 ` David Laight
@ 2026-05-20 22:05 ` Christophe Leroy (CS GROUP)
0 siblings, 0 replies; 6+ messages in thread
From: Christophe Leroy (CS GROUP) @ 2026-05-20 22:05 UTC (permalink / raw)
To: David Laight
Cc: Mingcong Bai, linux-kernel, Xi Ruoyao, Kexy Biscuit, stable,
kernel test robot, Madhavan Srinivasan, Michael Ellerman,
Nicholas Piggin, linuxppc-dev
Le 20/05/2026 à 20:43, David Laight a écrit :
> On Wed, 20 May 2026 15:14:40 +0200
> "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> wrote:
>
>> Le 17/05/2026 à 15:54, David Laight a écrit :
>>> On Sun, 17 May 2026 12:14:21 +0800
>>> Mingcong Bai <jeffbai@aosc.io> wrote:
>>>
>>>> Similar to commit b929926f01f2 ("sh: define __BIG_ENDIAN for math-emu"),
>>>> define __LITTLE_ENDIAN and __BIG_ENDIAN as 0 to mitigate build-time
>>>> warnings:
>>>>
>>>> ./include/math-emu/double.h:59:21: error: ‘__BIG_ENDIAN’ is not defined, evaluates to ‘0’ [-Werror=undef]
>>>> 59 | #if __BYTE_ORDER == __BIG_ENDIAN
>>>> |
>>>>
>>>> Cc: stable@vger.kernel.org
>>>> Fixes: 13da9e200fe4 ("Revert "endian: #define __BYTE_ORDER"")
>>>> Reported-by: kernel test robot <lkp@intel.com>
>>>> Closes: https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Foe-kbuild-all%2F202507301656.7FEX6J5W-lkp%40intel.com%2F&data=05%7C02%7Cchristophe.leroy2%40cs-soprasteria.com%7C3ed26b8c3d6449fdc29608deb69fac66%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C639148994069314641%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=FfFnXxMPXXxoOMM8fYU4df5gMjk3B2dPgQsjwUagaNA%3D&reserved=0
>>>> Signed-off-by: Mingcong Bai <jeffbai@aosc.io>
>>>> ---
>>>> arch/powerpc/include/asm/sfp-machine.h | 4 +++-
>>>> 1 file changed, 3 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
>>>> index 8b957aabb826d..db8525605c026 100644
>>>> --- a/arch/powerpc/include/asm/sfp-machine.h
>>>> +++ b/arch/powerpc/include/asm/sfp-machine.h
>>>> @@ -319,10 +319,12 @@
>>>> #define abort() \
>>>> return 0
>>>>
>>>> -#ifdef __BIG_ENDIAN
>>>> +#ifdef __BIG_ENDIAN__
>>>> #define __BYTE_ORDER __BIG_ENDIAN
>>>> +#define __LITTLE_ENDIAN 0
>>>> #else
>>>> #define __BYTE_ORDER __LITTLE_ENDIAN
>>>> +#define __BIG_ENDIAN 0
>>>> #endif
>>>
>>> I thought the expected/correct value for __BYTE_ORDER__ was either 1234 or 4321.
>>> (apart from pdp11's 2143).
>>
>> That's the case, in include/linux/kconfig.h we have:
>>
>> #ifdef CONFIG_CPU_BIG_ENDIAN
>> #define __BIG_ENDIAN 4321
>> #else
>> #define __LITTLE_ENDIAN 1234
>> #endif
>>
>> But as far as I understand the problem is that math-emu expects
>> __BIG_ENDIAN to be defined at all time as it has tests like:
>>
>> #if __BYTE_ORDER == __BIG_ENDIAN
>
> The gcc docs have (https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgcc.gnu.org%2Fonlinedocs%2Fcpp%2FCommon-Predefined-Macros.html&data=05%7C02%7Cchristophe.leroy2%40cs-soprasteria.com%7C3ed26b8c3d6449fdc29608deb69fac66%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C639148994069350793%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=D0BlZT73XnqHXHN2ukPFFUQw5lCCwaKfkmp6vMHz0Gk%3D&reserved=0):
>
> __BYTE_ORDER__
> __ORDER_LITTLE_ENDIAN__
> __ORDER_BIG_ENDIAN__
> __ORDER_PDP_ENDIAN__
>
> __BYTE_ORDER__ is defined to one of the values __ORDER_LITTLE_ENDIAN__, __ORDER_BIG_ENDIAN__, or __ORDER_PDP_ENDIAN__ to reflect the layout of multi-byte and multi-word quantities in memory. If __BYTE_ORDER__ is equal to __ORDER_LITTLE_ENDIAN__ or __ORDER_BIG_ENDIAN__, then multi-byte and multi-word quantities are laid out identically: the byte (word) at the lowest address is the least significant or most significant byte (word) of the quantity, respectively. If __BYTE_ORDER__ is equal to __ORDER_PDP_ENDIAN__, then bytes in 16-bit words are laid out in a little-endian fashion, whereas the 16-bit subwords of a 32-bit quantity are laid out in big-endian fashion.
>
> You should use these macros for testing like this:
>
> /* Test for a little-endian machine */
> #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
>
> The doc doesn't mention the value, but __ORDER_BIG_ENDIAN__ is 4321 (decimal).
>
> So the math-emu code is neither following gcc's rules or the kernel ones.
>
> Your change will break anything that currently does:
> #ifdef __BIG_ENDIAN
>
> Any change would have to be limited to code that is implementing math-emu.
asm/sfp-machine.h is only included by math-emu it seems, so the change
should be safe.
Apparently math-emu predates git history, not sure where it comes from.
Christophe
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-05-20 22:05 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2026-05-17 4:14 [PATCH] powerpc: define __LITTLE_ENDIAN and __BIG_ENDIAN for math-emu Mingcong Bai
2026-05-17 13:54 ` David Laight
2026-05-17 15:40 ` Xi Ruoyao
2026-05-20 13:14 ` Christophe Leroy (CS GROUP)
2026-05-20 18:43 ` David Laight
2026-05-20 22:05 ` Christophe Leroy (CS GROUP)
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