Failed to install mlton

[anta40 (Andre Tampubolon)]

$ sudo port install mlton
Password:
--->  Computing dependencies for mlton
The following dependencies will be installed:  mlton-bootstrap
Continue? [Y/n]: Y
--->  Fetching archive for mlton-bootstrap
Warning: Your DNS servers incorrectly claim to know the address of nonexistent hosts. This may cause checksum mismatches for some ports. See this page for more information: <https://trac.macports.org/wiki/MisbehavingServers>
--->  Attempting to fetch mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 from http://jog.id.packages.macports.org/macports/packages/mlton-bootstrap
--->  Attempting to fetch mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 from https://packages.macports.org/mlton-bootstrap
--->  Attempting to fetch mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 from https://mirror.sjtu.edu.cn/macports/packages/mlton-bootstrap
--->  Verifying checksums for mlton-bootstrap
Error: Failed to checksum mlton-bootstrap: mlton-20210117-1.amd64-darwin-19.6.gmp-homebrew.tgz does not exist in /opt/local/var/macports/distfiles/mlton-bootstrap
Error: See /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_lang_mlton-bootstrap/mlton-bootstrap/main.log for details.
Error: Follow https://guide.macports.org/#project.tickets if you believe there is a bug.
Error: Processing of port mlton failed

Examining the log, perhaps this is the cause:

$ cat /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_lang_mlton-bootstrap/mlton-bootstrap/main.log
...
...
:info:archivefetch --->  mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 doesn't seem to exist in /opt/local/var/macports/incoming/verified
:msg:archivefetch --->  Attempting to fetch mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 from http://jog.id.packages.macports.org/macports/packages/mlton-bootstrap
:debug:archivefetch Fetching archive failed: The requested URL returned error: 404
:msg:archivefetch --->  Attempting to fetch mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 from https://packages.macports.org/mlton-bootstrap
:debug:archivefetch Fetching archive failed: The requested URL returned error: 404
:msg:archivefetch --->  Attempting to fetch mlton-bootstrap-20210117_0.darwin_21.x86_64.tbz2 from https://mirror.sjtu.edu.cn/macports/packages/mlton-bootstrap
:debug:archivefetch Fetching archive failed: The requested URL returned error: 403
:debug:archivefetch Privilege de-escalation not attempted as not running as root.
:debug:archivefetch Skipping completed org.macports.fetch (mlton-bootstrap)
...

[ryandesign (Ryan Carsten Schmidt)]

Lack of a precompiled archive (because we only just set up the build machine and it hasn't yet gotten around to trying to build this port) is why the port is building from source on your machine, but that is not why checksums failed; lack of source archive is the reason. This shouldn't have happened but running sudo port clean mlton and trying again should either succeed or give a different error for us to investigate.