[PATCH 0/3] Fix debugging info for .S files

[PATCH 0/3] Fix debugging info for .S files

[Geoff Levand]

Hi Michal,

Here are a few small patches to fixup debug info gereration for .S files.  I
tested the generated vmlinux with the ARM Fast Model debugger and ARM64 target.

Please apply.

-Geoff

The following changes since commit 374b105797c3d4f29c685f3be535c35f5689b30e:

  Linux 3.13-rc3 (2013-12-06 09:34:04 -0800)

are available in the git repository at:

  git://git.linaro.org/people/geoff.levand/linux-kexec.git for-kbuild

for you to fetch changes up to e9d530c5b8b1c9a8510d9c8db8663aedc393de8f:

  mn10300: Remove redundent debugging info flag (2013-12-11 15:15:00 -0800)

----------------------------------------------------------------
Geoff Levand (3):
      kbuild: Fix debugging info generation for .S files
      frv: Remove redundent debugging info flag
      mn10300: Remove redundent debugging info flag

 Makefile              | 2 +-
 arch/frv/Makefile     | 1 -
 arch/mn10300/Makefile | 1 -
 3 files changed, 1 insertion(+), 3 deletions(-)

-- 
1.8.1.2

[PATCH 1/3] kbuild: Fix debugging info generation for .S files

[Geoff Levand]

Change the debuging info generation flag in KBUILD_AFLAGS from '-gdwarf-2' to
'-Wa,--gdwarf-2'.  This will properly generate the debugging info for .S files
when CONFIG_DEBUG_INFO=y.

It seems current gcc does not pass a '--gdwarf-2' option on to the assembler
when '-gdwarf-2' is on its command line (note the differece in the gcc and as
flags).  This change provides the correct assembler flag to gcc, and so does
not rely on gcc to emit a flag for the assembler.

Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 890392f..7308a6f 100644
--- a/Makefile
+++ b/Makefile
@@ -619,7 +619,7 @@ endif
 
 ifdef CONFIG_DEBUG_INFO
 KBUILD_CFLAGS	+= -g
-KBUILD_AFLAGS	+= -gdwarf-2
+KBUILD_AFLAGS	+= -Wa,--gdwarf-2
 endif
 
 ifdef CONFIG_DEBUG_INFO_REDUCED
-- 
1.8.1.2

Re: [PATCH 1/3] kbuild: Fix debugging info generation for .S files

[Michal Marek]

Dne 12.12.2013 00:34, Geoff Levand napsal(a):
> Change the debuging info generation flag in KBUILD_AFLAGS from '-gdwarf-2' to
> '-Wa,--gdwarf-2'.  This will properly generate the debugging info for .S files
> when CONFIG_DEBUG_INFO=y.
> 
> It seems current gcc does not pass a '--gdwarf-2' option on to the assembler
> when '-gdwarf-2' is on its command line (note the differece in the gcc and as
> flags).  This change provides the correct assembler flag to gcc, and so does
> not rely on gcc to emit a flag for the assembler.
> 
> Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
> ---
>  Makefile | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied to kbuild.git#kbuild, sorry for the delay.

Michal

[PATCH 2/3] frv: Remove redundent debugging info flag

[Geoff Levand]

The gereric makefile now sets '-Wa,--gdwarf2' in KBUILD_AFLAGS, so
this setting is no longer needed in arch makefiles.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
---
 arch/frv/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/frv/Makefile b/arch/frv/Makefile
index 4d1b1e9..5b838db 100644
--- a/arch/frv/Makefile
+++ b/arch/frv/Makefile
@@ -78,7 +78,6 @@ KBUILD_AFLAGS	+= -mno-fdpic
 # and disable optimisations that are unhelpful whilst debugging
 ifdef CONFIG_DEBUG_INFO
 #KBUILD_CFLAGS	+= -O1
-KBUILD_AFLAGS	+= -Wa,--gdwarf2
 endif
 
 head-y		:= arch/frv/kernel/head.o
-- 
1.8.1.2

Re: [PATCH V2 2/3] frv: Remove redundant debugging info flag

[Geoff Levand]

The generic makefile now sets '-Wa,--gdwarf2' in KBUILD_AFLAGS, so
this setting is no longer needed in arch makefiles.

Also remove a commented out addition of a -O1 to KBUILD_CFLAGS, and
comment text relating to these removed lines.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
---
v2: Removed unused CONFIG_DEBUG_INFO conditional and related text comment.

 arch/frv/Makefile | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/frv/Makefile b/arch/frv/Makefile
index 4d1b1e9..2a8fb73 100644
--- a/arch/frv/Makefile
+++ b/arch/frv/Makefile
@@ -74,13 +74,6 @@ KBUILD_CFLAGS	+= -mno-fdpic -mgpr-32 -msoft-float -mno-media
 KBUILD_CFLAGS	+= -ffixed-fcc3 -ffixed-cc3 -ffixed-gr15 -ffixed-icc2
 KBUILD_AFLAGS	+= -mno-fdpic
 
-# make sure the .S files get compiled with debug info
-# and disable optimisations that are unhelpful whilst debugging
-ifdef CONFIG_DEBUG_INFO
-#KBUILD_CFLAGS	+= -O1
-KBUILD_AFLAGS	+= -Wa,--gdwarf2
-endif
-
 head-y		:= arch/frv/kernel/head.o
 
 core-y		+= arch/frv/kernel/ arch/frv/mm/
-- 
1.8.1.2

Re: [PATCH V2 2/3] frv: Remove redundant debugging info flag

[Michal Marek]

On 28.1.2014 02:48, Geoff Levand wrote:
> The generic makefile now sets '-Wa,--gdwarf2' in KBUILD_AFLAGS, so
> this setting is no longer needed in arch makefiles.
> 
> Also remove a commented out addition of a -O1 to KBUILD_CFLAGS, and
> comment text relating to these removed lines.
> 
> Cc: David Howells <dhowells@redhat.com>
> Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
> ---
> v2: Removed unused CONFIG_DEBUG_INFO conditional and related text comment.

Thanks, I added v2 of 2/3 and 3/3 to kbuild.git#kbuild.

Michal

[PATCH 3/3] mn10300: Remove redundent debugging info flag

[Geoff Levand]

The gereric makefile now sets '-Wa,--gdwarf2' in KBUILD_AFLAGS, so
this setting is no longer needed in arch makefiles.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
---
 arch/mn10300/Makefile | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/mn10300/Makefile b/arch/mn10300/Makefile
index a3d0fef..f5a9db9 100644
--- a/arch/mn10300/Makefile
+++ b/arch/mn10300/Makefile
@@ -97,7 +97,6 @@ endef
 # that are unhelpful whilst debugging.
 ifdef CONFIG_DEBUG_INFO
 #KBUILD_CFLAGS	+= -O1
-KBUILD_AFLAGS	+= -Wa,--gdwarf2
 endif
 
 #
-- 
1.8.1.2

Re: [PATCH 3/3] mn10300: Remove redundent debugging info flag

[Michal Marek]

Dne 12.12.2013 00:34, Geoff Levand napsal(a):
> The gereric makefile now sets '-Wa,--gdwarf2' in KBUILD_AFLAGS, so
> this setting is no longer needed in arch makefiles.
> 
> Cc: David Howells <dhowells@redhat.com>
> Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
> ---
>  arch/mn10300/Makefile | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/mn10300/Makefile b/arch/mn10300/Makefile
> index a3d0fef..f5a9db9 100644
> --- a/arch/mn10300/Makefile
> +++ b/arch/mn10300/Makefile
> @@ -97,7 +97,6 @@ endef
>  # that are unhelpful whilst debugging.
>  ifdef CONFIG_DEBUG_INFO
>  #KBUILD_CFLAGS	+= -O1
> -KBUILD_AFLAGS	+= -Wa,--gdwarf2
>  endif

This leaves only a commented-out assignment in the ifdef block. Just
remove it completely together with the outdated comment above. Same for
the frv Makefile.

Michal

[PATCH V2 3/3] mn10300: Remove redundant debugging info flag

[Geoff Levand]

The generic makefile now sets '-Wa,--gdwarf2' in KBUILD_AFLAGS, so
this setting is no longer needed in arch makefiles.

Also remove a commented out addition of a -O1 to KBUILD_CFLAGS, and
comment text relating to these removed lines.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Geoff Levand <geoff@infradead.org> for Huawei, Linaro
---
v2: Removed unused CONFIG_DEBUG_INFO conditional and related text comment.

 arch/mn10300/Makefile | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/arch/mn10300/Makefile b/arch/mn10300/Makefile
index a3d0fef..3f1ea5d 100644
--- a/arch/mn10300/Makefile
+++ b/arch/mn10300/Makefile
@@ -92,14 +92,6 @@ define archhelp
   echo  '* zImage        - Compressed kernel image (arch/$(ARCH)/boot/zImage)'
 endef
 
-# If you make sure the .S files get compiled with debug info,
-# uncomment the following to disable optimisations
-# that are unhelpful whilst debugging.
-ifdef CONFIG_DEBUG_INFO
-#KBUILD_CFLAGS	+= -O1
-KBUILD_AFLAGS	+= -Wa,--gdwarf2
-endif
-
 #
 # include the appropriate processor- and unit-specific headers
 #
-- 
1.8.1.2