On Fri, Jan 29, 2021 at 04:44:00PM -0800, Nick Desaulniers wrote: > Modifies CONFIG_DEBUG_INFO_DWARF4 to be a member of a choice which is > the default. Does so in a way that's forward compatible with existing > configs, and makes adding future versions more straightforward. > > GCC since ~4.8 has defaulted to this DWARF version implicitly. > > Suggested-by: Arvind Sankar <nived...@alum.mit.edu> > Suggested-by: Fangrui Song <mask...@google.com> > Suggested-by: Nathan Chancellor <nat...@kernel.org> > Suggested-by: Masahiro Yamada <masahi...@kernel.org> > Signed-off-by: Nick Desaulniers <ndesaulni...@google.com>
One comment below: Reviewed-by: Nathan Chancellor <nat...@kernel.org> > --- > Makefile | 5 ++--- > lib/Kconfig.debug | 16 +++++++++++----- > 2 files changed, 13 insertions(+), 8 deletions(-) > > diff --git a/Makefile b/Makefile > index 95ab9856f357..d2b4980807e0 100644 > --- a/Makefile > +++ b/Makefile > @@ -830,9 +830,8 @@ ifneq ($(LLVM_IAS),1) > KBUILD_AFLAGS += -Wa,-gdwarf-2 It is probably worth a comment somewhere that assembly files will still have DWARF v2. > endif > > -ifdef CONFIG_DEBUG_INFO_DWARF4 > -DEBUG_CFLAGS += -gdwarf-4 > -endif > +dwarf-version-$(CONFIG_DEBUG_INFO_DWARF4) := 4 > +DEBUG_CFLAGS += -gdwarf-$(dwarf-version-y) > > 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 e906ea906cb7..94c1a7ed6306 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -256,13 +256,19 @@ 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_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" > -- > 2.30.0.365.g02bc693789-goog >
