lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 3 Dec 2020 14:56:43 -0800 From: Nick Desaulniers <ndesaulniers@...gle.com> To: Arvind Sankar <nivedita@...m.mit.edu> Cc: Masahiro Yamada <masahiroy@...nel.org>, Linux Kbuild mailing list <linux-kbuild@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org>, clang-built-linux <clang-built-linux@...glegroups.com>, linux-toolchains@...r.kernel.org Subject: Re: [PATCH] Kbuild: implement support for DWARF5 On Tue, Nov 3, 2020 at 4:17 PM Arvind Sankar <nivedita@...m.mit.edu> wrote: > > On Tue, Nov 03, 2020 at 04:05:36PM -0800, Nick Desaulniers wrote: > > On Tue, Nov 3, 2020 at 4:00 PM Arvind Sankar <nivedita@...m.mit.edu> wrote: > > > > > > On Wed, Oct 21, 2020 at 06:21:06PM -0700, Nick Desaulniers wrote: > > > > Further -gdwarf-X where X is an unsupported value doesn't > > > > produce an error in $(CC). > > > > > > Do you have more details here? On godbolt.org, gcc does report an error > > > for unsupported dwarf versions. > > > > > > https://godbolt.org/z/G35798 > > > > > > gcc does not seem to pass the -gdwarf-* options to the assembler when > > > compiling C source. For assembler, gcc will pass an appropriate option > > > depending on the version of binutils it was configured with: if the > > > assembler doesn't support dwarf-5 it can call it with --gdwarf2 for eg. > > > > > > If the user is using a properly configured toolchain it doesn't look > > > like it should be an issue to just use cc-option? > > > > I wrote the base patch back in May, and didn't revisit until recently. > > I could have sworn the cc-option silently failed for the check > > cc-option does, which is /dev/null input. I need to recheck that, but > > it doesn't hurt to simply include it for now, which I've done in a v2 > > I'm about to send. > > -- > > Thanks, > > ~Nick Desaulniers > > This is giving me deja vu about the -gz=zlib option. > > Didn't Masahiro fix the cc-option issue with > 4d0831e8a029 ("kconfig: unify cc-option and as-option") > > The existing -Wa,-gdwarf-2 in the Makefile seems bogus, btw. GCC 4.9.0 > at least appears to pass on --gdwarf2 automatically. It looks like we don't need -Wa,-gdwarf-2 when -gdwarf-2 is set. So I can probably drop +DEBUG_CFLAGS += $(dwarf-aflag) from v2. Will retest though. -- Thanks, ~Nick Desaulniers
Powered by blists - more mailing lists