How do you include debug info for assembly files in the Linux kernel?

Question

For debug info, I have these config options enabled:

/Volumes/git/linux (master)*$ grep CONFIG_DEBUG build/.config | grep -v ^#
CONFIG_DEBUG_ALIGN_RODATA=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_INFO=y
CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
CONFIG_DEBUG_LL_INCLUDE="mach/debug-macro.S"

However the vmlinux file only includes debug info for .c and .h files and not .S files.

Is there a standard way to get debug info for the assembly files included in vmlinux?

update 8/2/2022:

I found that in scripts/Makefile.debug if you use LLVM/clang then debug info is excluded from assembly files for some reason.

ifndef CONFIG_AS_IS_LLVM
KBUILD_AFLAGS   += -Wa,-gdwarf-2
endif

and removing the ifndef line fixed the missing debug info for me.

Why is ifndef CONFIG_AS_IS_LLVM there?

Answer 1

if building with llvm clang, remove ifndef CONFIG_AS_IS_LLVM and endif from around the KBUILD_AFLAGS

diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug
index 9f39b0130551f..1a26df0538b5b 100644
--- a/scripts/Makefile.debug
+++ b/scripts/Makefile.debug
@@ -6,9 +6,7 @@ else
 DEBUG_CFLAGS   += -g
 endif
 
-ifndef CONFIG_AS_IS_LLVM
 KBUILD_AFLAGS  += -Wa,-gdwarf-2
-endif
 
 ifndef CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4