FAILED: patch "[PATCH] Kbuild: do not emit debug info for assembly with LLVM_IAS=1" failed to apply to 5.9-stable tree

The patch below does not apply to the 5.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b8a9092330da2030496ff357272f342eb970d51b Mon Sep 17 00:00:00 2001
From: Nick Desaulniers <[email protected]>
Date: Mon, 9 Nov 2020 10:35:28 -0800
Subject: [PATCH] Kbuild: do not emit debug info for assembly with LLVM_IAS=1

Clang's integrated assembler produces the warning for assembly files:

warning: DWARF2 only supports one section per compilation unit

If -Wa,-gdwarf-* is unspecified, then debug info is not emitted for assembly sources (it is still emitted for C sources). This will be re-enabled for newer DWARF versions in a follow up patch.

Enables defconfig+CONFIG_DEBUG_INFO to build cleanly with LLVM=1 LLVM_IAS=1 for x86_64 and arm64.

Cc <[email protected]>

Link https://github.com/ClangBuiltLinux/linux/issues/716

Reported-by Dmitry Golovin <[email protected]>

Reported-by Nathan Chancellor <[email protected]>

Suggested-by Dmitry Golovin <[email protected]>

Suggested-by Nathan Chancellor <[email protected]>

Suggested-by Sedat Dilek <[email protected]>

Reviewed-by Fangrui Song <[email protected]>

Reviewed-by Nathan Chancellor <[email protected]>

Signed-off-by Nick Desaulniers <[email protected]>

Signed-off-by Masahiro Yamada <[email protected]>

Makefile +2 -0

index 87d659d3c8de..ae1592c1f5d6 100644
@@ -828,7 +828,9 @@ else
 DEBUG_CFLAGS   += -g
 endif
 
+ifneq ($(LLVM_IAS),1)
 KBUILD_AFLAGS  += -Wa,-gdwarf-2
+endif
 
 ifdef CONFIG_DEBUG_INFO_DWARF4
 DEBUG_CFLAGS   += -gdwarf-4