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Date:   Mon, 19 Sep 2022 10:30:30 -0700
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Subject: [PATCH v4] Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT
From:   Nick Desaulniers <ndesaulniers@google.com>
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     Michal Marek <michal.lkml@markovi.net>,
        Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        clang-built-linux <llvm@lists.linux.dev>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Andi Kleen <ak@linux.intel.com>,
        Dmitrii Bundin <dmitrii.bundin.a@gmail.com>,
        Fangrui Song <maskray@google.com>,
        Nathan Chancellor <nathan@kernel.org>
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Dmitrii, Fangrui, and Mashahiro note:

  Before GCC 11 and Clang 12 -gsplit-dwarf implicitly uses -g2.

Fix CONFIG_DEBUG_INFO_SPLIT for gcc-11+ & clang-12+ which now need -g
specified in order for -gsplit-dwarf to work at all.

-gsplit-dwarf has been mutually exclusive with -g since support for
CONFIG_DEBUG_INFO_SPLIT was introduced in
commit 866ced950bcd ("kbuild: Support split debug info v4")
I don't think it ever needed to be.

Link: https://lore.kernel.org/lkml/20220815013317.26121-1-dmitrii.bundin.a@gmail.com/
Link: https://lore.kernel.org/lkml/CAK7LNARPAmsJD5XKAw7m_X2g7Fi-CAAsWDQiP7+ANBjkg7R7ng@mail.gmail.com/
Link: https://reviews.llvm.org/D80391
Cc: Andi Kleen <ak@linux.intel.com>
Reported-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Reported-by: Fangrui Song <maskray@google.com>
Reported-by: Masahiro Yamada <masahiroy@kernel.org>
Suggested-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
Changes v3 -> v4:
* Split into its own patch; we don't have any out of line assembler
  files using .debug_* or .cfi_* directives that would produce
  meaningful debug info in .dwo files.

 scripts/Makefile.debug | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug
index 9f39b0130551..26d6a9d97a20 100644
--- a/scripts/Makefile.debug
+++ b/scripts/Makefile.debug
@@ -1,9 +1,7 @@
-DEBUG_CFLAGS	:=
+DEBUG_CFLAGS	:= -g
 
 ifdef CONFIG_DEBUG_INFO_SPLIT
 DEBUG_CFLAGS	+= -gsplit-dwarf
-else
-DEBUG_CFLAGS	+= -g
 endif
 
 ifndef CONFIG_AS_IS_LLVM
-- 
2.37.3.968.ga6b4b080e4-goog