Comment 8 for bug 1594452

gcc-5 5.4.0-5ubuntu1~16.04 from ppa:ubuntu-toolchain-r/ppa does accept vulcan as an -mcpu option, and it does pass the correct -march settings down to the assembler:

$ gcc -v hello.c -o hello 2>&1 | grep ' as '
 as -v -EL -mabi=lp64 -o /tmp/ccgyMnhl.o /tmp/cchw8EFH.s
$ gcc -mcpu=vulcan -v hello.c -o hello 2>&1 | grep ' as '
 as -v -EL -march=armv8.1-a+crypto -mabi=lp64 -o /tmp/ccgkHPq1.o /tmp/cc32DdK2.s

binutils 2.26.1-1ubuntu1~16.04 from proposed also accepts -mcpu vulcan now:

$ (gcc -Wa,-mcpu=vulcan -mcpu=vulcan -v hello.c -o hello 2>&1 && echo exitcode $? 1>&2)| grep ' as '
 as -v -EL -march=armv8.1-a+crypto -mabi=lp64 -mcpu=vulcan -o /tmp/cc2Hf3Ve.o /tmp/ccMVgC69.s
exitcode 0

I expected gcc -mcpu=vulcan to pass down -mcpu=vulcan to the assembler as well, but it didn't. I tested using -mcpu=xgene1 instead, and that also does not pass -mcpu=xgene1 down to the assembler, so I assume this is normal.