armv8l not detected

[tcely]

The alpinelinux armhf build died with an error requesting the cpu flag be set.

>>> botan: Checking sha512sums...
Botan-2.5.0.tgz: OK
>>> botan: Unpacking /var/cache/distfiles/Botan-2.5.0.tgz...
   INFO: ./configure.py invoked with options "--prefix=/usr --mandir=/usr/share/man --with-boost --with-bzip2 --with-lzma --with-openmp --with-openssl --with-sqlite3 --with-zlib"
   INFO: Autodetected platform information: OS="Linux" machine="armv8l" proc=""
   INFO: Guessing target OS is linux (use --os to set)
   INFO: Guessing to use compiler gcc (use --cc or CXX to set)
  ERROR: Could not determine target CPU; set with --cpu
>>> ERROR: botan: all failed

From: http://build.alpinelinux.org/buildlogs/build-edge-armhf/testing/botan/botan-2.5.0-r0.log

[randombit]

Can you post uname -a?

[clandmeter]

We are using an aarch64 machine in 32bit mode to build for armhf so the machine type will show armv8l.

[clandmeter]

ref: alpinelinux/aports#4049

[randombit]

I was not familiar with arvm8l so I had to do some reading about this. I'm putting some notes here both for my own reference later on, and also so you can correct me if anything is wrong.

• Aarch32 is ARMv8 running in 32-bit mode. It is instruction compatible with ARMv7-A. Here the Aarch32 ABI is identified as armv8l.

• Since Aarch32 and ARMv7-A are compatible, you are running a native toolchain rather than a crosscompiler.

So I think we should add arvm8l to the ARM32 block rather than ARM64 since this is not Aarch64.

(I see now the Alpine PR has changed to just use --cpu option everywhere - if that works then that is ideal.)

[tcely]

@randombit The uname output from that machine is:

$ uname -a >&2
| Linux build-edge-armhf 4.4.19 #2 SMP Mon Sep 5 11:05:13 GMT 2016 armv8l Linux

I believe due to either the existing aliases or the actual names of the files, just setting --cpu="$CARCH" will do what we want.

[clandmeter]

@randombit correct this is native not cross compile. Adding it to the arm32 block would make auto detection work so no need specify the cpu flag.

[randombit]

Fixed by #1544 thank you