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[PATCH v1] perf build: Add -funsigned-char to default CFLAGS

Ian Rogers posted 1 patch 1 month ago 
tools/perf/Makefile.config | 1 +
1 file changed, 1 insertion(+)
[PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Posted by Ian Rogers 1 month ago 
Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
chars unsigned by default in the Linux kernel. To avoid similar kinds
of bugs and warnings, make unsigned chars the default for the perf tool.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/Makefile.config | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index a8dc72cfe48e..3820bdf73f43 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -349,6 +349,7 @@ CORE_CFLAGS += -fno-omit-frame-pointer
 CORE_CFLAGS += -Wall
 CORE_CFLAGS += -Wextra
 CORE_CFLAGS += -std=gnu11
+CORE_CFLAGS += -funsigned-char
 
 CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
 CXXFLAGS += -Wall
-- 
2.53.0.473.g4a7958ca14-goog
Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Posted by Namhyung Kim 1 week ago 
On Fri, 06 Mar 2026 11:19:08 -0800, Ian Rogers wrote:
> Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
> chars unsigned by default in the Linux kernel. To avoid similar kinds
> of bugs and warnings, make unsigned chars the default for the perf tool.
> 
> 
Applied to perf-tools-next, thanks!

Best regards,
Namhyung
Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Posted by Ian Rogers 2 weeks, 5 days ago 
On Fri, Mar 6, 2026 at 11:19 AM Ian Rogers <irogers@google.com> wrote:
>
> Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
> chars unsigned by default in the Linux kernel. To avoid similar kinds
> of bugs and warnings, make unsigned chars the default for the perf tool.
>
> Signed-off-by: Ian Rogers <irogers@google.com>

Ping.

Thanks,
Ian

> ---
>  tools/perf/Makefile.config | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> index a8dc72cfe48e..3820bdf73f43 100644
> --- a/tools/perf/Makefile.config
> +++ b/tools/perf/Makefile.config
> @@ -349,6 +349,7 @@ CORE_CFLAGS += -fno-omit-frame-pointer
>  CORE_CFLAGS += -Wall
>  CORE_CFLAGS += -Wextra
>  CORE_CFLAGS += -std=gnu11
> +CORE_CFLAGS += -funsigned-char
>
>  CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
>  CXXFLAGS += -Wall
> --
> 2.53.0.473.g4a7958ca14-goog
>
Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Posted by Namhyung Kim 1 week, 6 days ago 
On Fri, Mar 20, 2026 at 04:00:56PM -0700, Ian Rogers wrote:
> On Fri, Mar 6, 2026 at 11:19 AM Ian Rogers <irogers@google.com> wrote:
> >
> > Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
> > chars unsigned by default in the Linux kernel. To avoid similar kinds
> > of bugs and warnings, make unsigned chars the default for the perf tool.
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>

Do you know what the actual bug was?

Thanks,
Namhyung

> 
> > ---
> >  tools/perf/Makefile.config | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> > index a8dc72cfe48e..3820bdf73f43 100644
> > --- a/tools/perf/Makefile.config
> > +++ b/tools/perf/Makefile.config
> > @@ -349,6 +349,7 @@ CORE_CFLAGS += -fno-omit-frame-pointer
> >  CORE_CFLAGS += -Wall
> >  CORE_CFLAGS += -Wextra
> >  CORE_CFLAGS += -std=gnu11
> > +CORE_CFLAGS += -funsigned-char
> >
> >  CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
> >  CXXFLAGS += -Wall
> > --
> > 2.53.0.473.g4a7958ca14-goog
> >
Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Posted by Ian Rogers 1 week, 6 days ago 
On Thu, Mar 26, 2026 at 3:17 PM Namhyung Kim <namhyung@kernel.org> wrote:
>
> On Fri, Mar 20, 2026 at 04:00:56PM -0700, Ian Rogers wrote:
> > On Fri, Mar 6, 2026 at 11:19 AM Ian Rogers <irogers@google.com> wrote:
> > >
> > > Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
> > > chars unsigned by default in the Linux kernel. To avoid similar kinds
> > > of bugs and warnings, make unsigned chars the default for the perf tool.
> > >
> > > Signed-off-by: Ian Rogers <irogers@google.com>
>
> Do you know what the actual bug was?

I don't, my motivation was to try to avoid sashiko warnings about
issues that occur with signed chars.

Thanks,
Ian

> Thanks,
> Namhyung
>
> >
> > > ---
> > >  tools/perf/Makefile.config | 1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> > > index a8dc72cfe48e..3820bdf73f43 100644
> > > --- a/tools/perf/Makefile.config
> > > +++ b/tools/perf/Makefile.config
> > > @@ -349,6 +349,7 @@ CORE_CFLAGS += -fno-omit-frame-pointer
> > >  CORE_CFLAGS += -Wall
> > >  CORE_CFLAGS += -Wextra
> > >  CORE_CFLAGS += -std=gnu11
> > > +CORE_CFLAGS += -funsigned-char
> > >
> > >  CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
> > >  CXXFLAGS += -Wall
> > > --
> > > 2.53.0.473.g4a7958ca14-goog
> > >
Re: [PATCH v1] perf build: Add -funsigned-char to default CFLAGS
Posted by Ian Rogers 1 week, 1 day ago 
On Thu, Mar 26, 2026 at 4:18 PM Ian Rogers <irogers@google.com> wrote:
>
> On Thu, Mar 26, 2026 at 3:17 PM Namhyung Kim <namhyung@kernel.org> wrote:
> >
> > On Fri, Mar 20, 2026 at 04:00:56PM -0700, Ian Rogers wrote:
> > > On Fri, Mar 6, 2026 at 11:19 AM Ian Rogers <irogers@google.com> wrote:
> > > >
> > > > Commit 3bc753c06dd0 ("kbuild: treat char as always unsigned") made
> > > > chars unsigned by default in the Linux kernel. To avoid similar kinds
> > > > of bugs and warnings, make unsigned chars the default for the perf tool.
> > > >
> > > > Signed-off-by: Ian Rogers <irogers@google.com>
> >
> > Do you know what the actual bug was?
>
> I don't, my motivation was to try to avoid sashiko warnings about
> issues that occur with signed chars.

Ping.

Thanks,
Ian

> Thanks,
> Ian
>
> > Thanks,
> > Namhyung
> >
> > >
> > > > ---
> > > >  tools/perf/Makefile.config | 1 +
> > > >  1 file changed, 1 insertion(+)
> > > >
> > > > diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> > > > index a8dc72cfe48e..3820bdf73f43 100644
> > > > --- a/tools/perf/Makefile.config
> > > > +++ b/tools/perf/Makefile.config
> > > > @@ -349,6 +349,7 @@ CORE_CFLAGS += -fno-omit-frame-pointer
> > > >  CORE_CFLAGS += -Wall
> > > >  CORE_CFLAGS += -Wextra
> > > >  CORE_CFLAGS += -std=gnu11
> > > > +CORE_CFLAGS += -funsigned-char
> > > >
> > > >  CXXFLAGS += -std=gnu++17 -fno-exceptions -fno-rtti
> > > >  CXXFLAGS += -Wall
> > > > --
> > > > 2.53.0.473.g4a7958ca14-goog
> > > >

Patchew 2.1-devel-ea86937

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