[PATCH 0/2] gcc-plugins: disable plugins when gmp.h is unavailable

[PATCH 0/2] gcc-plugins: disable plugins when gmp.h is unavailable

[Thomas Weißschuh]

Without gmp.h the plugin build fails.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
Thomas Weißschuh (2):
      kbuild: add host-cc-option helper
      gcc-plugins: disable plugins when gmp.h is unavailable

 scripts/Kconfig.include     | 4 ++++
 scripts/gcc-plugins/Kconfig | 1 +
 2 files changed, 5 insertions(+)
---
base-commit: 855684c7d938c2442f07eabc154e7532b4c1fbf9
change-id: 20240312-gcc-plugins-gmp-efab1a8d05c0

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh@linutronix.de>

[PATCH 1/2] kbuild: add host-cc-option helper

[Thomas Weißschuh]

This helper works the same as cc-option but for the host compiler.
It will be used by the gcc-plugins configuration to check for the gmp.h
header.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 scripts/Kconfig.include | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
index 3ee8ecfb8c04..84368e23b072 100644
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -27,6 +27,10 @@ failure = $(if-success,$(1),n,y)
 # Return y if the compiler supports <flag>, n otherwise
 cc-option = $(success,trap "rm -rf .tmp_$$" EXIT; mkdir .tmp_$$; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$/tmp.o)
 
+# $(host-cc-option,<flag>)
+# Return y if the host compiler supports <flag>, n otherwise
+host-cc-option = $(success,trap "rm -rf .tmp_$$" EXIT; mkdir .tmp_$$; $(HOSTCC) -Werror $(HOSTCFLAGS) $(1) -c -x c /dev/null -o .tmp_$$/tmp.o)
+
 # $(ld-option,<flag>)
 # Return y if the linker supports <flag>, n otherwise
 ld-option = $(success,$(LD) -v $(1))

-- 
2.44.0

[PATCH 2/2] gcc-plugins: disable plugins when gmp.h is unavailable

[Thomas Weißschuh]

The header gmp.h is meant to be picked up from the host system.

When it is unavailable the plugin build fails:

In file included from ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/gcc-plugin.h:28,
                 from ../scripts/gcc-plugins/gcc-common.h:7,
                 from ../scripts/gcc-plugins/stackleak_plugin.c:30:
../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/system.h:703:10: fatal error: gmp.h: No such file or directory
  703 | #include <gmp.h>
      |          ^~~~~~~

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
---
 scripts/gcc-plugins/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
index e383cda05367..a664fb5cdde5 100644
--- a/scripts/gcc-plugins/Kconfig
+++ b/scripts/gcc-plugins/Kconfig
@@ -10,6 +10,7 @@ menuconfig GCC_PLUGINS
 	depends on HAVE_GCC_PLUGINS
 	depends on CC_IS_GCC
 	depends on $(success,test -e $(shell,$(CC) -print-file-name=plugin)/include/plugin-version.h)
+	depends on $(host-cc-option,-include gmp.h)
 	default y
 	help
 	  GCC plugins are loadable modules that provide extra features to the

-- 
2.44.0

Re: [PATCH 2/2] gcc-plugins: disable plugins when gmp.h is unavailable

[Kees Cook]

On Tue, Mar 12, 2024 at 04:03:30PM +0100, Thomas Weißschuh wrote:
> The header gmp.h is meant to be picked up from the host system.
> 
> When it is unavailable the plugin build fails:
> 
> In file included from ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/gcc-plugin.h:28,
>                  from ../scripts/gcc-plugins/gcc-common.h:7,
>                  from ../scripts/gcc-plugins/stackleak_plugin.c:30:
> ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/system.h:703:10: fatal error: gmp.h: No such file or directory
>   703 | #include <gmp.h>
>       |          ^~~~~~~
> 
> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> ---
>  scripts/gcc-plugins/Kconfig | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
> index e383cda05367..a664fb5cdde5 100644
> --- a/scripts/gcc-plugins/Kconfig
> +++ b/scripts/gcc-plugins/Kconfig
> @@ -10,6 +10,7 @@ menuconfig GCC_PLUGINS
>  	depends on HAVE_GCC_PLUGINS
>  	depends on CC_IS_GCC
>  	depends on $(success,test -e $(shell,$(CC) -print-file-name=plugin)/include/plugin-version.h)
> +	depends on $(host-cc-option,-include gmp.h)

Why does the prior depends not fail? That's where plugin detection is
happening.

-- 
Kees Cook

Re: [PATCH 2/2] gcc-plugins: disable plugins when gmp.h is unavailable

[Masahiro Yamada]

On Wed, Mar 13, 2024 at 6:53 AM Kees Cook <keescook@chromium.org> wrote:
>
> On Tue, Mar 12, 2024 at 04:03:30PM +0100, Thomas Weißschuh wrote:
> > The header gmp.h is meant to be picked up from the host system.
> >
> > When it is unavailable the plugin build fails:
> >
> > In file included from ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/gcc-plugin.h:28,
> >                  from ../scripts/gcc-plugins/gcc-common.h:7,
> >                  from ../scripts/gcc-plugins/stackleak_plugin.c:30:
> > ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/system.h:703:10: fatal error: gmp.h: No such file or directory
> >   703 | #include <gmp.h>
> >       |          ^~~~~~~
> >
> > Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> > ---
> >  scripts/gcc-plugins/Kconfig | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
> > index e383cda05367..a664fb5cdde5 100644
> > --- a/scripts/gcc-plugins/Kconfig
> > +++ b/scripts/gcc-plugins/Kconfig
> > @@ -10,6 +10,7 @@ menuconfig GCC_PLUGINS
> >       depends on HAVE_GCC_PLUGINS
> >       depends on CC_IS_GCC
> >       depends on $(success,test -e $(shell,$(CC) -print-file-name=plugin)/include/plugin-version.h)
> > +     depends on $(host-cc-option,-include gmp.h)
>
> Why does the prior depends not fail? That's where plugin detection is
> happening.
>
> --
> Kees Cook
>



This patch set should be rejected.


It was already discussed in the past.
Just install a proper package, then gcc-plugin will work.

https://lore.kernel.org/all/CAHk-=wjjiYjCp61gdAMpDOsUBU-A2hFFKJoVx5VAC7yV4K6WYg@mail.gmail.com/






-- 
Best Regards
Masahiro Yamada

Re: [PATCH 2/2] gcc-plugins: disable plugins when gmp.h is unavailable

[Thomas Weißschuh]

On Wed, Mar 13, 2024 at 12:47:59PM +0900, Masahiro Yamada wrote:
> On Wed, Mar 13, 2024 at 6:53 AM Kees Cook <keescook@chromium.org> wrote:
> >
> > On Tue, Mar 12, 2024 at 04:03:30PM +0100, Thomas Weißschuh wrote:
> > > The header gmp.h is meant to be picked up from the host system.
> > >
> > > When it is unavailable the plugin build fails:
> > >
> > > In file included from ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/gcc-plugin.h:28,
> > >                  from ../scripts/gcc-plugins/gcc-common.h:7,
> > >                  from ../scripts/gcc-plugins/stackleak_plugin.c:30:
> > > ../crosstools/gcc-13.2.0-nolibc/i386-linux/bin/../lib/gcc/i386-linux/13.2.0/plugin/include/system.h:703:10: fatal error: gmp.h: No such file or directory
> > >   703 | #include <gmp.h>
> > >       |          ^~~~~~~
> > >
> > > Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
> > > ---
> > >  scripts/gcc-plugins/Kconfig | 1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
> > > index e383cda05367..a664fb5cdde5 100644
> > > --- a/scripts/gcc-plugins/Kconfig
> > > +++ b/scripts/gcc-plugins/Kconfig
> > > @@ -10,6 +10,7 @@ menuconfig GCC_PLUGINS
> > >       depends on HAVE_GCC_PLUGINS
> > >       depends on CC_IS_GCC
> > >       depends on $(success,test -e $(shell,$(CC) -print-file-name=plugin)/include/plugin-version.h)
> > > +     depends on $(host-cc-option,-include gmp.h)
> >
> > Why does the prior depends not fail? That's where plugin detection is
> > happening.
> >
> > --
> > Kees Cook
> 
> This patch set should be rejected.
> 
> 
> It was already discussed in the past.
> Just install a proper package, then gcc-plugin will work.
> 
> https://lore.kernel.org/all/CAHk-=wjjiYjCp61gdAMpDOsUBU-A2hFFKJoVx5VAC7yV4K6WYg@mail.gmail.com/

Thanks for the pointer.

As there is already consensus I agree that the patches should not be used.

Thomas