On Sat, Sep 24, 2022 at 11:20 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Fri, Sep 23, 2022 at 7:12 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote: > > > > This patch still misses the debug info for *.S files > > for the combination of LLVM_IAS=0 and > > CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y > > because, as the comment says, Clang does not pass -g down to GAS. > > > > > > With "[v4] Makefile.debug: set -g unconditional on CONFIG_DEBUG_INFO_SPLIT" > > and this one applied, > > > > > > > > $ grep CONFIG_DEBUG_INFO_DWARF .config > > CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y > > # CONFIG_DEBUG_INFO_DWARF4 is not set > > # CONFIG_DEBUG_INFO_DWARF5 is not set > > $ make LLVM=1 LLVM_IAS=0 arch/x86/kernel/irqflags.o > > SYNC include/config/auto.conf.cmd > > SYSHDR arch/x86/include/generated/asm/unistd_32_ia32.h > > SYSHDR arch/x86/include/generated/asm/unistd_64_x32.h > > SYSTBL arch/x86/include/generated/asm/syscalls_64.h > > HOSTCC arch/x86/tools/relocs_32.o > > [snip] > > AS arch/x86/kernel/irqflags.o > > $ objdump -h arch/x86/kernel/irqflags.o | grep debug > > $ > > > > > > > > > > > > > > > > > > I think the following fix-up is needed on top. > > > > > > > > > > diff --git a/scripts/Makefile.debug b/scripts/Makefile.debug > > index d6aecd78b942..8cf1cb22dd93 100644 > > --- a/scripts/Makefile.debug > > +++ b/scripts/Makefile.debug > > @@ -1,4 +1,5 @@ > > -DEBUG_CFLAGS := -g > > +DEBUG_CFLAGS := > > +debug-flags-y := -g > > > > ifdef CONFIG_DEBUG_INFO_SPLIT > > DEBUG_CFLAGS += -gsplit-dwarf > > > > > > > > > > Then, I can see the debug sections. > > > > > > > > $ make LLVM=1 LLVM_IAS=0 arch/x86/kernel/irqflags.o > > CALL scripts/checksyscalls.sh > > DESCEND objtool > > AS arch/x86/kernel/irqflags.o > > $ objdump -h arch/x86/kernel/irqflags.o | grep debug > > 6 .debug_line 00000050 0000000000000000 0000000000000000 0000008f 2**0 > > 7 .debug_info 0000002e 0000000000000000 0000000000000000 000000f8 2**0 > > 8 .debug_abbrev 00000014 0000000000000000 0000000000000000 000001d0 2**0 > > 9 .debug_aranges 00000030 0000000000000000 0000000000000000 000001f0 2**4 > > 10 .debug_str 0000004d 0000000000000000 0000000000000000 00000250 2**0 > > > > > > > > > > > > If you agree, I can locally fix it up as such. > > Ah, sorry I missed testing that combination. Thanks for your > thoroughness. Yes please apply that diff on top. > -- > Thanks, > ~Nick Desaulniers Applied to linux-kbuild with the fixup. -- Best Regards Masahiro Yamada
