On Fri, Aug 19, 2022 at 8:42 PM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > Is any of this really necessary? Consider the case if CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y. Prior to GCC11/Clang12 -gsplit-dwarf implied -g2. So on newer compilers with -gsplit-dwarf in use there would be no debug symbols produced. -gdwarf-4/5 still implies -g2, but in case CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y neither of the options are set. So it seems like a reasonable choice to provide a debug info level config that would explicitly set the level without relying on implicits. The default value of the config is set to -g2 to not change the build behavior that was before introducing the option. And it works for both older and newer versions of GCC/Clang in the same way. The benefits of the -g1 option are indeed questionable except that it produces an image with ~20% less in size. > It seems like a great way to bloat > vmlinux artifacts built with CONFIG_DEBUG_INFO even further. The defaults were chosen to not change the build behavior that was before introducing the options. Or did you mean something else? > The > above link mentions "when debugging with GDB." In that case, please > don't add new Kconfigs for these; just set -g3 when > CONFIG_GDB_SCRIPTS=y. CONFIG_GDB_SCRIPTS does not necessarily mean that -g3 is wanted, -g2 (default) is usually a reasonable choice. The -g3 option is very useful when debugging macro-intensive code, but requires much more disk space to build. I documented it explicitly in the help section of DEBUG_INFO_LEVEL. GCC and Clang use different options to include macro definitions so it was handled depending on the compiler used. Regards Dmitrii
