[0/3] fix debug info for asm and DEBUG_INFO_SPLIT

Message

Nick Desaulniers Aug. 26, 2022, 6:10 p.m. UTC

Alexey reported that the fraction of unknown filename instances in
kallsyms grew from ~0.3% to ~10% recently; Bill and Greg tracked it down
to assembler defined symbols, which regressed as a result of:

commit b8a9092330da ("Kbuild: do not emit debug info for assembly with LLVM_IAS=1")

In that commit, I allude to restoring debug info for assembler defined
symbols in a follow up patch, but it seems I forgot to do so in

commit a66049e2cf0e ("Kbuild: make DWARF version a choice")

Do so requires a fixup for as-option, which seems to be failing when
used in scripts/Makefile.debug.

Also includes a fix for DEBUG_INFO_SPLIT while I'm here.  Dmitrii
reports that this has been broken since gcc-11+ & clang-12+. I'm
guessing no one uses this .config option...since no one else has
reported it being broken yet...

Nick Desaulniers (3):
  Makefile.compiler: s/KBUILD_CFLAGS/KBUILD_AFLAGS/ for as-option
  Makefile.debug: re-enable debug info for .S files
  Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT

 arch/x86/boot/compressed/Makefile |  5 +++--
 scripts/Makefile.compiler         |  6 +++---
 scripts/Makefile.debug            | 26 +++++++++++++++++++-------
 3 files changed, 25 insertions(+), 12 deletions(-)