[PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[Heinrich Schuchardt]

When building with GCC 15.2 the following warning show up:

    scripts/dtc/libfdt/fdt_overlay.c:422:21: warning:
    assignment discards ‘const’ qualifier from pointer target type
    [-Wdiscarded-qualifiers]
      422 |                 sep = memchr(fixup_str, ':', fixup_len);
          |                     ^
    scripts/dtc/libfdt/fdt_overlay.c:432:21: warning:
    assignment discards ‘const’ qualifier from pointer target type
    [-Wdiscarded-qualifiers]
      432 |                 sep = memchr(name, ':', fixup_len);
          |                     ^

Define sep as const char *.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
---
 scripts/dtc/libfdt/fdt_overlay.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/dtc/libfdt/fdt_overlay.c b/scripts/dtc/libfdt/fdt_overlay.c
index ee64f0b8110..e40cfe8c3c7 100644
--- a/scripts/dtc/libfdt/fdt_overlay.c
+++ b/scripts/dtc/libfdt/fdt_overlay.c
@@ -407,7 +407,8 @@ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off,
 		const char *fixup_str = value;
 		uint32_t path_len, name_len;
 		uint32_t fixup_len;
-		char *sep, *endptr;
+		const char *sep;
+		char *endptr;
 		int poffset, ret;
 
 		fixup_end = memchr(value, '\0', len);
-- 
2.53.0

Re: [PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 957 bytes --]

On Sat, Apr 18, 2026 at 08:15:10PM +0200, Heinrich Schuchardt wrote:

> When building with GCC 15.2 the following warning show up:
> 
>     scripts/dtc/libfdt/fdt_overlay.c:422:21: warning:
>     assignment discards ‘const’ qualifier from pointer target type
>     [-Wdiscarded-qualifiers]
>       422 |                 sep = memchr(fixup_str, ':', fixup_len);
>           |                     ^
>     scripts/dtc/libfdt/fdt_overlay.c:432:21: warning:
>     assignment discards ‘const’ qualifier from pointer target type
>     [-Wdiscarded-qualifiers]
>       432 |                 sep = memchr(name, ':', fixup_len);
>           |                     ^
> 
> Define sep as const char *.
> 
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
> ---
>  scripts/dtc/libfdt/fdt_overlay.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

Is this something already fixed in upstream dtc?

-- 
Tom

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: [PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[Heinrich Schuchardt]

On 4/18/26 21:09, Tom Rini wrote:
> On Sat, Apr 18, 2026 at 08:15:10PM +0200, Heinrich Schuchardt wrote:
> 
>> When building with GCC 15.2 the following warning show up:
>>
>>      scripts/dtc/libfdt/fdt_overlay.c:422:21: warning:
>>      assignment discards ‘const’ qualifier from pointer target type
>>      [-Wdiscarded-qualifiers]
>>        422 |                 sep = memchr(fixup_str, ':', fixup_len);
>>            |                     ^
>>      scripts/dtc/libfdt/fdt_overlay.c:432:21: warning:
>>      assignment discards ‘const’ qualifier from pointer target type
>>      [-Wdiscarded-qualifiers]
>>        432 |                 sep = memchr(name, ':', fixup_len);
>>            |                     ^
>>
>> Define sep as const char *.
>>
>> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
>> ---
>>   scripts/dtc/libfdt/fdt_overlay.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> Is this something already fixed in upstream dtc?
> 

9a1c801a1a3c ("Fix discarded const qualifiers")
in git://git.kernel.org/pub/scm/utils/dtc/dtc.git
implements a similar change.

But the patch is not applicable:

error: scripts/dtc/fdtput.c: does not exist in index
error: scripts/dtc/meson.build: does not exist in index

The change in fdt_overlay.c is identical.

Best regards

Heinrich

Re: [PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 1913 bytes --]

On Sat, Apr 18, 2026 at 09:46:47PM +0200, Heinrich Schuchardt wrote:
> On 4/18/26 21:09, Tom Rini wrote:
> > On Sat, Apr 18, 2026 at 08:15:10PM +0200, Heinrich Schuchardt wrote:
> > 
> > > When building with GCC 15.2 the following warning show up:
> > > 
> > >      scripts/dtc/libfdt/fdt_overlay.c:422:21: warning:
> > >      assignment discards ‘const’ qualifier from pointer target type
> > >      [-Wdiscarded-qualifiers]
> > >        422 |                 sep = memchr(fixup_str, ':', fixup_len);
> > >            |                     ^
> > >      scripts/dtc/libfdt/fdt_overlay.c:432:21: warning:
> > >      assignment discards ‘const’ qualifier from pointer target type
> > >      [-Wdiscarded-qualifiers]
> > >        432 |                 sep = memchr(name, ':', fixup_len);
> > >            |                     ^
> > > 
> > > Define sep as const char *.
> > > 
> > > Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
> > > ---
> > >   scripts/dtc/libfdt/fdt_overlay.c | 3 ++-
> > >   1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > Is this something already fixed in upstream dtc?
> > 
> 
> 9a1c801a1a3c ("Fix discarded const qualifiers")
> in git://git.kernel.org/pub/scm/utils/dtc/dtc.git
> implements a similar change.
> 
> But the patch is not applicable:
> 
> error: scripts/dtc/fdtput.c: does not exist in index
> error: scripts/dtc/meson.build: does not exist in index
> 
> The change in fdt_overlay.c is identical.

Yeah, we need to re-sync with the kernel again, and there's some other
issue to sort out. I don't recall what, just that someone else had
looked and it wasn't a "update, no changes required". So we should look
in to that I think. I don't know if gcc-15.2.x has released with a bug
fix for building all of our platforms or not yet:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121588

-- 
Tom

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: [PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[Heinrich Schuchardt]

On 4/18/26 21:49, Tom Rini wrote:
> On Sat, Apr 18, 2026 at 09:46:47PM +0200, Heinrich Schuchardt wrote:
>> On 4/18/26 21:09, Tom Rini wrote:
>>> On Sat, Apr 18, 2026 at 08:15:10PM +0200, Heinrich Schuchardt wrote:
>>>
>>>> When building with GCC 15.2 the following warning show up:
>>>>
>>>>       scripts/dtc/libfdt/fdt_overlay.c:422:21: warning:
>>>>       assignment discards ‘const’ qualifier from pointer target type
>>>>       [-Wdiscarded-qualifiers]
>>>>         422 |                 sep = memchr(fixup_str, ':', fixup_len);
>>>>             |                     ^
>>>>       scripts/dtc/libfdt/fdt_overlay.c:432:21: warning:
>>>>       assignment discards ‘const’ qualifier from pointer target type
>>>>       [-Wdiscarded-qualifiers]
>>>>         432 |                 sep = memchr(name, ':', fixup_len);
>>>>             |                     ^
>>>>
>>>> Define sep as const char *.
>>>>
>>>> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
>>>> ---
>>>>    scripts/dtc/libfdt/fdt_overlay.c | 3 ++-
>>>>    1 file changed, 2 insertions(+), 1 deletion(-)
>>>
>>> Is this something already fixed in upstream dtc?
>>>
>>
>> 9a1c801a1a3c ("Fix discarded const qualifiers")
>> in git://git.kernel.org/pub/scm/utils/dtc/dtc.git
>> implements a similar change.
>>
>> But the patch is not applicable:
>>
>> error: scripts/dtc/fdtput.c: does not exist in index
>> error: scripts/dtc/meson.build: does not exist in index
>>
>> The change in fdt_overlay.c is identical.
> 
> Yeah, we need to re-sync with the kernel again, and there's some other
> issue to sort out. I don't recall what, just that someone else had
> looked and it wasn't a "update, no changes required". So we should look
> in to that I think. I don't know if gcc-15.2.x has released with a bug
> fix for building all of our platforms or not yet:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121588
> 

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121588 is marked as closed 
and backported.

releases/gcc-15.2.0-665-g4886dd899bb
4886dd899bbb ("lto: Fix SegFault in ICF caused by missing body")

This is in Debian and Ubuntu since release 15.2.0-15.
Ubuntu 26.04 is at 15.2.0-16ubuntu1.

Best regards

Heinrich

Re: [PATCH 1/1] scripts/dtc: avoid discarded qualifiers in overlay_fixup_phandle

[Tom Rini]

[-- Attachment #1: Type: text/plain, Size: 2767 bytes --]

On Sat, Apr 18, 2026 at 10:01:29PM +0200, Heinrich Schuchardt wrote:
> On 4/18/26 21:49, Tom Rini wrote:
> > On Sat, Apr 18, 2026 at 09:46:47PM +0200, Heinrich Schuchardt wrote:
> > > On 4/18/26 21:09, Tom Rini wrote:
> > > > On Sat, Apr 18, 2026 at 08:15:10PM +0200, Heinrich Schuchardt wrote:
> > > > 
> > > > > When building with GCC 15.2 the following warning show up:
> > > > > 
> > > > >       scripts/dtc/libfdt/fdt_overlay.c:422:21: warning:
> > > > >       assignment discards ‘const’ qualifier from pointer target type
> > > > >       [-Wdiscarded-qualifiers]
> > > > >         422 |                 sep = memchr(fixup_str, ':', fixup_len);
> > > > >             |                     ^
> > > > >       scripts/dtc/libfdt/fdt_overlay.c:432:21: warning:
> > > > >       assignment discards ‘const’ qualifier from pointer target type
> > > > >       [-Wdiscarded-qualifiers]
> > > > >         432 |                 sep = memchr(name, ':', fixup_len);
> > > > >             |                     ^
> > > > > 
> > > > > Define sep as const char *.
> > > > > 
> > > > > Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
> > > > > ---
> > > > >    scripts/dtc/libfdt/fdt_overlay.c | 3 ++-
> > > > >    1 file changed, 2 insertions(+), 1 deletion(-)
> > > > 
> > > > Is this something already fixed in upstream dtc?
> > > > 
> > > 
> > > 9a1c801a1a3c ("Fix discarded const qualifiers")
> > > in git://git.kernel.org/pub/scm/utils/dtc/dtc.git
> > > implements a similar change.
> > > 
> > > But the patch is not applicable:
> > > 
> > > error: scripts/dtc/fdtput.c: does not exist in index
> > > error: scripts/dtc/meson.build: does not exist in index
> > > 
> > > The change in fdt_overlay.c is identical.
> > 
> > Yeah, we need to re-sync with the kernel again, and there's some other
> > issue to sort out. I don't recall what, just that someone else had
> > looked and it wasn't a "update, no changes required". So we should look
> > in to that I think. I don't know if gcc-15.2.x has released with a bug
> > fix for building all of our platforms or not yet:
> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121588
> > 
> 
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121588 is marked as closed and
> backported.
> 
> releases/gcc-15.2.0-665-g4886dd899bb
> 4886dd899bbb ("lto: Fix SegFault in ICF caused by missing body")
> 
> This is in Debian and Ubuntu since release 15.2.0-15.
> Ubuntu 26.04 is at 15.2.0-16ubuntu1.

And not in
https://www.kernel.org/pub/tools/crosstool/files/bin/x86_64/15.2.0/ so
not available to CI yet. So I would like to see if we can move up our
dtc backport of the kernel backport, by the time there's new crosstools
available.

-- 
Tom

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]