On Wed, Jan 20, 2021 at 9:40 PM Nathan Chancellor <natechancellor@xxxxxxxxx> wrote: > > On Fri, Jan 15, 2021 at 01:06:15PM -0800, Nick Desaulniers wrote: > > Modifies CONFIG_DEBUG_INFO_DWARF4 to be a member of a choice. Adds an > > explicit CONFIG_DEBUG_INFO_DWARF2, which is the default. Does so in a > > way that's forward compatible with existing configs, and makes adding > > future versions more straightforward. > > > > Suggested-by: Arvind Sankar <nivedita@xxxxxxxxxxxx> > > Suggested-by: Fangrui Song <maskray@xxxxxxxxxx> > > Suggested-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> > > Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> > > --- > > Makefile | 13 ++++++------- > > lib/Kconfig.debug | 21 ++++++++++++++++----- > > 2 files changed, 22 insertions(+), 12 deletions(-) > > > > diff --git a/Makefile b/Makefile > > index d49c3f39ceb4..4eb3bf7ee974 100644 > > --- a/Makefile > > +++ b/Makefile > > @@ -826,13 +826,12 @@ else > > DEBUG_CFLAGS += -g > > endif > > > > -ifneq ($(LLVM_IAS),1) > > -KBUILD_AFLAGS += -Wa,-gdwarf-2 > > -endif > > Aren't you regressing this with this patch? Why is the hunk from 3/3 > that adds > > ifdef CONFIG_CC_IS_CLANG > ifneq ($(LLVM_IAS),1) > > not in this patch? > Nice catch Nathan. Just FYI: The patch... "kbuild: Remove $(cc-option,-gdwarf-4) dependency from DEBUG_INFO_DWARF4" ... has now entered kbuild-next. ( This patch is included in this patch-series. ) So should we point to this one and add a comment? Thinking of a next version of this DWARF5 support patch-series. - Sedat - [1] https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/commit/?h=kbuild&id=3f4d8ce271c7082be75bacbcbd2048aa78ce2b44 > > -ifdef CONFIG_DEBUG_INFO_DWARF4 > > -DEBUG_CFLAGS += -gdwarf-4 > > -endif > > +dwarf-version-$(CONFIG_DEBUG_INFO_DWARF2) := 2 > > +dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4 > > +DEBUG_CFLAGS += -gdwarf-$(dwarf-version-y) > > +# Binutils 2.35+ required for -gdwarf-4+ support. > > +dwarf-aflag := $(call as-option,-Wa$(comma)-gdwarf-$(dwarf-version-y)) > > +KBUILD_AFLAGS += $(dwarf-aflag) > > > > ifdef CONFIG_DEBUG_INFO_REDUCED > > DEBUG_CFLAGS += $(call cc-option, -femit-struct-debug-baseonly) \ > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > > index dd7d8d35b2a5..e80770fac4f0 100644 > > --- a/lib/Kconfig.debug > > +++ b/lib/Kconfig.debug > > @@ -256,13 +256,24 @@ config DEBUG_INFO_SPLIT > > to know about the .dwo files and include them. > > Incompatible with older versions of ccache. > > > > +choice > > + prompt "DWARF version" > > + help > > + Which version of DWARF debug info to emit. > > + > > +config DEBUG_INFO_DWARF2 > > + bool "Generate DWARF Version 2 debuginfo" > > + help > > + Generate DWARF v2 debug info. > > + > > config DEBUG_INFO_DWARF4 > > - bool "Generate dwarf4 debuginfo" > > + bool "Generate DWARF Version 4 debuginfo" > > help > > - Generate dwarf4 debug info. This requires recent versions > > - of gcc and gdb. It makes the debug information larger. > > - But it significantly improves the success of resolving > > - variables in gdb on optimized code. > > + Generate DWARF v4 debug info. This requires gcc 4.5+ and gdb 7.0+. > > + It makes the debug information larger, but it significantly > > + improves the success of resolving variables in gdb on optimized code. > > + > > +endchoice # "DWARF version" > > > > config DEBUG_INFO_BTF > > bool "Generate BTF typeinfo" > > -- > > 2.30.0.284.gd98b1dd5eaa7-goog > >
