cmd/compile: wrong instantiation of imported type causes typechecker error

What version of Go are you using (go version)?

$ go version
go version devel go1.18-8ac5cbe05d Fri Oct 1 04:32:04 2021 +0000 windows/amd64

Does this issue reproduce with the latest release?

No.

What operating system and processor architecture are you using (go env)?

go env Output

$ go env

What did you do?

The reproducer is quite complex, so I pushed it into the repo https://github.com/tdakkota/goissue-48716.
I tried to simplify it, but had no success. It seems bug appears only if Map interface is imported from another package.

What did you expect to see?

Successful compilation.

What did you see instead?

<autogenerated>:1: cannot use cb (type func(alg.Pair[int,struct{}]) bool) as type func(alg.Pair[.shape.int_0,.shape.struct{}_1]) bool in argument to maps.HashMap[.shape.int_0,.shape.struct{}_1].Iterate

[mknyszek]

CC @griesemer @mdempsky @danscales

[cuonglm]

I can't reproduce this with:

go version devel go1.18-3bbc82371e Sat Oct 2 17:29:46 2021 +0000 darwin/arm64

[danscales]

Hmm, did you go to the sets directory and run 'go test'. I am able to reproduce at current master, including 3bbc823:

% cd sets
% go test
# github.com/tdakkota/goissue-48716/sets [github.com/tdakkota/goissue-48716/sets.test]
<autogenerated>:1: cannot use cb (type func(maps.Pair[int,struct{}]) bool) as type func(maps.Pair[.shape.int_0,.shape.struct{}_1]) bool in argument to maps.HashMap[.shape.int_0,.shape.struct{}_1].Iterate
FAIL    github.com/tdakkota/goissue-48716/sets [build failed]

I am working on it (roughly know where the problem is, but not fixed yet).

[cuonglm]

Hmm, did you go to the sets directory and run 'go test'. I am able to reproduce at current master, including 3bbc823:

% cd sets
% go test
# github.com/tdakkota/goissue-48716/sets [github.com/tdakkota/goissue-48716/sets.test]
<autogenerated>:1: cannot use cb (type func(maps.Pair[int,struct{}]) bool) as type func(maps.Pair[.shape.int_0,.shape.struct{}_1]) bool in argument to maps.HashMap[.shape.int_0,.shape.struct{}_1].Iterate
FAIL    github.com/tdakkota/goissue-48716/sets [build failed]

I am working on it (roughly know where the problem is, but not fixed yet).

Oh right, I only did go build.

[gopherbot]

Change https://golang.org/cl/355250 mentions this issue: cmd/compile: some fixes in type substituter for Instantiate