[MacPorts] #64059: mono will not install on macOS 12 on M1 hardware

[MacPorts]

#64059: mono will not install on macOS 12 on M1 hardware
---------------------+---------------------------------
  Reporter:  gctwnl  |      Owner:  MarcusCalhoun-Lopez
      Type:  defect  |     Status:  assigned
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:  2.7.1
Resolution:          |   Keywords:  monterey arm64
      Port:  mono    |
---------------------+---------------------------------

Comment (by davidben):

 I ran into this as well, and can reproduce this building from the tarball
 directly. It looks like UCONTEXT_REG_R0 is getting expanded from here:

 https://github.com/mono/mono/blob/mono-6.12.0.122/mono/utils/mono-
 sigcontext.h#L384

 Yet presumably this is the right expansion for aarch64:

 https://github.com/mono/mono/blob/mono-6.12.0.122/mono/utils/mono-
 sigcontext.h#L466

 Looks like the immediate problem is the config.sub, or some other part of
 autotools, shipped in the Mono tarball is too old and is guessing a target
 triple of arm-apple-darwin21.2.0 instead of aarch64-apple-darwin21.2.0. If
 I autoreconf -fvi, I get a little further along in the build, though it
 seems to break later on for some bootstrapping reason. ./configure
 --build=aarch64-apple-darwin21.2.0 similarly avoids the outdated
 config.sub but runs into the bootstrapping problem.

 Given the latest release doesn't yet include
 https://github.com/mono/mono/pull/20166, this is perhaps not expected to
 work yet. https://github.com/mono/mono/pull/20166#discussion_r745633487
 may also become an issue.

-- 
Ticket URL: <https://trac.macports.org/ticket/64059#comment:3>
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