On Wed, Oct 02, 2019 at 09:47:41AM -0700, Nick Desaulniers wrote: > On Wed, Oct 2, 2019 at 12:55 AM Ard Biesheuvel > <ard.biesheuvel@xxxxxxxxxx> wrote: > > > > Now that the Clang compiler has taken it upon itself to police the > > compiler command line, and reject combinations for arguments it views > > as incompatible, the AEGIS128 no longer builds correctly, and errors > > out like this: > > > > clang-10: warning: ignoring extension 'crypto' because the 'armv7-a' > > architecture does not support it [-Winvalid-command-line-argument] > > > > So let's switch to armv8-a instead, which matches the crypto-neon-fp-armv8 > > FPU profile we specify. Since neither were actually supported by GCC > > versions before 4.8, let's tighten the Kconfig dependencies as well so > > we won't run into errors when building with an ancient compiler. > > > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> > > Thank you Ard, this fixes the build error for us. Do you know if the > "crypto extensions" are mandatory ISA extensions? I think they are optional (or at least most of them). > I'm running into some inconsistencies between how clang parses target > arch between command line flag, function __attribute__, assembler > directive, and disassembler. I see arch's like: armv8-a+crc, > armv8-a+sve, armv8-a+fp16, armv8-a+memtag, armv8-a+lse, but I'm not > familiar with the `+...` part of the target arch. This page shows the possible combinations: https://sourceware.org/binutils/docs/as/AArch64-Extensions.html#AArch64-Extensions Basically if it's an optional feature in ARMv8.0, you pass armv8-a+... For optional features only in higher versions, it would be armv8.5-a+memtag. The table above also states whether it's enabled by default (i.e. mandatory) in an architecture version. SB for example is supported from 8.0 but only required in 8.5. -- Catalin
