From: Alan Donovan <adonovan@google.com>
Date: Tue, 28 Nov 2023 21:07:01 +0000 (-0500)
Subject: go/types: include AST in instantiatedIdent panic message
X-Git-Tag: go1.22rc1~141
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=6111acc8e6bc96f5ca0fa58adf4a0226fff3dd28;p=gostls13.git

go/types: include AST in instantiatedIdent panic message

Updates golang/go#63933

Change-Id: I3ff71e92d124c850eb8b4d136e163bf5786897a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/545615
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Alan Donovan <adonovan@google.com>
---

diff --git a/src/go/types/check.go b/src/go/types/check.go
index 4a5f0731df..85fd0744d2 100644
--- a/src/go/types/check.go
+++ b/src/go/types/check.go
@@ -14,6 +14,7 @@ import (
 	"go/token"
 	"internal/godebug"
 	. "internal/types/errors"
+	"strings"
 )
 
 // nopos indicates an unknown position
@@ -618,7 +619,12 @@ func instantiatedIdent(expr ast.Expr) *ast.Ident {
 	case *ast.SelectorExpr:
 		return x.Sel
 	}
-	panic("instantiated ident not found")
+
+	// extra debugging of #63933
+	var buf strings.Builder
+	buf.WriteString("instantiated ident not found; please report: ")
+	ast.Fprint(&buf, token.NewFileSet(), expr, ast.NotNilFilter)
+	panic(buf.String())
 }
 
 func (check *Checker) recordDef(id *ast.Ident, obj Object) {