[PATCH v1] powerpc: Error on assembly warnings

[Andrew Donnellan]

On Tue, 2024-03-26 at 15:44 +1100, Benjamin Gray wrote:
> We currently enable -Werror on the arch/powerpc subtree. However this
> only catches C warnings. Assembly warnings are logged, but the make
> invocation will still succeed. This can allow incorrect syntax such
> as
> 
>   ori r3, r4, r5
> 
> to be compiled without catching that the assembler is treating r5
> as the immediate value 5.
> 
> To prevent this in assembly files and inline assembly, add the
> -fatal-warnings option to assembler invocations.
> 
> Signed-off-by: Benjamin Gray <bgray at linux.ibm.com>

Seems like a good idea to me!

Reviewed-by: Andrew Donnellan <ajd at linux.ibm.com>
Tested-by: Andrew Donnellan <ajd at linux.ibm.com>

> ---
>  arch/powerpc/Kbuild | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/Kbuild b/arch/powerpc/Kbuild
> index 22cd0d55a892..da862e9558bc 100644
> --- a/arch/powerpc/Kbuild
> +++ b/arch/powerpc/Kbuild
> @@ -1,5 +1,6 @@
>  # SPDX-License-Identifier: GPL-2.0
> -subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
> +subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror -Wa,-fatal-warnings
> +subdir-asflags-$(CONFIG_PPC_WERROR) := -Wa,-fatal-warnings
>  
>  obj-y += kernel/
>  obj-y += mm/

-- 
Andrew Donnellan    OzLabs, ADL Canberra
ajd at linux.ibm.com   IBM Australia Limited