Re: [PATCH 2/2] Kbuild: Add a option to enable dwarf4

Michal Marek
2014-07-30T13:38:26Z

On 2014-07-30 01:11, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
>
> I found that a lot of unresolvable variables when using gdb on the kernel
> become resolvable when dwarf4 is enabled. So add a Kconfig flag to enable it.
>
> It definitely increases the debug information size, but on the other
> hand this isn't so bad when debug fusion is used.
>
> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> ---
> Makefile | 3 +++
> lib/Kconfig.debug | 9 +++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/Makefile b/Makefile
> index 6a717cd..6cdf3f0 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -696,6 +696,9 @@ KBUILD_CFLAGS += -g
> endif
> KBUILD_AFLAGS += -Wa,-gdwarf-2
> endif
> +ifdef CONFIG_DEBUG_INFO_DWARF4
> +KBUILD_CFLAGS += -gdwarf-4
> +endif

Make it $(call cc-option,-gdwarf-4), so as not to break allmodconfig
with older GCCs. Otherwise the patch is OK.

Michal