Issue #19481 has been updated by k0kubun (Takashi Kokubun).
Status changed from Assigned to Closed
Accepting @nobu's answer as the solution.
I personally just blew away the entire build directory, but a colleague of mine did
`./autogen.sh`, `./configure`, and `make` and it worked. It might work without
`./autogen.sh` as @hsbt said, but I haven't tested it.
----------------------------------------
Bug #19481: make: *** No rule to make target 'defs/universal.mk'. Stop.
https://bugs.ruby-lang.org/issues/19481#change-102184
* Author: duerst (Martin Dürst)
* Status: Closed
* Priority: Normal
* Assignee: k0kubun (Takashi Kokubun)
* ruby -v: ruby 3.1.0dev (2021-06-03T06:59:33Z master 7e14762159) [x86_64-linux]
* Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN
----------------------------------------
When I tried to compile Ruby with `make up; make`, I got the message in the Subject.
The line before said:
`GNUmakefile:30: defs/universal.mk: No such file or directory`
Below is the start of the output. git seems to correctly download new stuff. But
apparently something is missing. I hope this problem can be fixed soon.
```
duerst@Kloentalersee:~/15ruby$ make up; make
remote: Enumerating objects: 4839, done.
remote: Counting objects: 100% (4839/4839), done.
remote: Compressing objects: 100% (2467/2467), done.
remote: Total 4839 (delta 3132), reused 2965 (delta 2049), pack-reused 0
Receiving objects: 100% (4839/4839), 3.20 MiB | 2.53 MiB/s, done.
Resolving deltas: 100% (3132/3132), completed with 391 local objects.
From git.ruby-lang.org:ruby
cb40432c74..f68580890f master -> origin/master
a4ab9921a1..0602df301c ruby_3_1 -> origin/ruby_3_1
31819e82c8..f93c7b9f58 ruby_3_2 -> origin/ruby_3_2
8f9b896b51..926b22ef5c refs/notes/commits -> refs/notes/commits
Updating cb40432c74..f68580890f
Fast-forward
```
--
https://bugs.ruby-lang.org/