Re: [PATCH] purgatory: fix disabling debug info

[Masahiro Yamada]

On Mon, Mar 27, 2023 at 12:35 AM Alyssa Ross <hi@xxxxxxxxx> wrote:
>
> Since 32ef9e5054ec, -Wa,-gdwarf-2 is no longer used in KBUILD_AFLAGS.
> Instead, it includes -g, the appropriate -gdwarf-* flag, and also the
> -Wa versions of both of those if building with Clang and GNU as.  As a
> result, debug info was being generated for the purgatory objects, even
> though the intention was that it not be.
>
> Fixes: 32ef9e5054ec ("Makefile.debug: re-enable debug info for .S files")
> Signed-off-by: Alyssa Ross <hi@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
>  arch/riscv/purgatory/Makefile | 12 ++++++------
>  arch/x86/purgatory/Makefile   |  4 ++--
>  2 files changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/arch/riscv/purgatory/Makefile b/arch/riscv/purgatory/Makefile
> index d16bf715a586..97001798fa19 100644
> --- a/arch/riscv/purgatory/Makefile
> +++ b/arch/riscv/purgatory/Makefile
> @@ -84,12 +84,12 @@ CFLAGS_string.o                     += $(PURGATORY_CFLAGS)
>  CFLAGS_REMOVE_ctype.o          += $(PURGATORY_CFLAGS_REMOVE)
>  CFLAGS_ctype.o                 += $(PURGATORY_CFLAGS)
>
> -AFLAGS_REMOVE_entry.o          += -Wa,-gdwarf-2
> -AFLAGS_REMOVE_memcpy.o         += -Wa,-gdwarf-2
> -AFLAGS_REMOVE_memset.o         += -Wa,-gdwarf-2
> -AFLAGS_REMOVE_strcmp.o         += -Wa,-gdwarf-2
> -AFLAGS_REMOVE_strlen.o         += -Wa,-gdwarf-2
> -AFLAGS_REMOVE_strncmp.o                += -Wa,-gdwarf-2
> +AFLAGS_REMOVE_entry.o          += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5
> +AFLAGS_REMOVE_memcpy.o         += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5
> +AFLAGS_REMOVE_memset.o         += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5
> +AFLAGS_REMOVE_strcmp.o         += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5
> +AFLAGS_REMOVE_strlen.o         += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5
> +AFLAGS_REMOVE_strncmp.o                += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5


You can merge these into a single line:

 asflags-remove-y += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5


Or, a slightly shorter but tricky way is:

 asflags-remove-y += $(foreach x, -g -gdwarf-4 -gdwarf-5, $(x) -Wa,$(x))


>  $(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
>                 $(call if_changed,ld)
> diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
> index 17f09dc26381..f1b1ef6c4cbf 100644
> --- a/arch/x86/purgatory/Makefile
> +++ b/arch/x86/purgatory/Makefile
> @@ -69,8 +69,8 @@ CFLAGS_sha256.o                       += $(PURGATORY_CFLAGS)
>  CFLAGS_REMOVE_string.o         += $(PURGATORY_CFLAGS_REMOVE)
>  CFLAGS_string.o                        += $(PURGATORY_CFLAGS)
>
> -AFLAGS_REMOVE_setup-x86_$(BITS).o      += -Wa,-gdwarf-2
> -AFLAGS_REMOVE_entry64.o                        += -Wa,-gdwarf-2
> +AFLAGS_REMOVE_setup-x86_$(BITS).o      += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5
> +AFLAGS_REMOVE_entry64.o                        += -g -gdwarf-4 -gdwarf-5 -Wa,-g -Wa,-gdwarf4 -Wa,-gdwarf-5


Ditto.


Thanks.



>  $(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
>                 $(call if_changed,ld)
>
> base-commit: da8e7da11e4ba758caf4c149cc8d8cd555aefe5f
> --
> 2.37.1
>


-- 
Best Regards
Masahiro Yamada