With this, 'tinygo test' in github.com/pkg/errors at least compiles and passes a few tests:
$ git clone github.com/pkg/errors
$ cd errors
$ tinygo test -c
$ for a in $(go test -list Test | grep Test); do ./errors.test -test.run $a -test.v > $a.log 2>&1; done
$ grep -l PASS *.log | wc -l
19
$ grep -l FAIL *.log | wc -l
11
For https://github.com/tinygo-org/tinygo/issues/2445
2c7ea98ccf