Re: OABI [was Re: COMPAT_NETBSD32 in GENERIC.common]

[Greg Troxel <gdt%lexort.com@localhost>]

I have spiffed up the evbarm port page.  However, there's a lot of magic
that includes sections in a template, and that is not playing well with
my attempt to use a table.   So it may be best to review the table
source, which I'll include here. until such time as somebody who is good
at our wiki and templates can fix it or explain to me how.

My big takeaways were

  earmv4 does not assume thumb, so supports strongarm

  earm is effectively an alias for earmv4 and I can't explain why it exists.

https://wiki.netbsd.org/ports/evbarm/


[[!table data="""
MACHINE_ARCH |bits | ARM architecture version            |ABI
arm          |32   |?                                    |oabi
earm         |32   |armv4 (effectively an alias)         |eabi
earmv4       |32   |armv4 (no thumb, so ok on strongarm) | eabi
earmv5       |32   |armv5t                               |eabi
earmv6       |32   |armv6                                |eabi
earmv7       |32   |armv7                                |eabi
aarch64      |64   |armv8                                |\todo ? eabi
"""]]

\todo Explain why, if we have armv4, and this is confusing, we still have earm as a MACHINE_ARCH.

\todo Explain why aarch64 is a MACHINE_ARCH, when it seems like it
should be something like armv8hf_64.

\todo Explain if MACHINE_ARCH values correspond to a particular
argument to some CPU selection command in gcc (and/or clang).