diff --git a/src/cmd/compile/internal/ir/expr.go b/src/cmd/compile/internal/ir/expr.go
index 345828c1638..fe13a840962 100644
--- a/src/cmd/compile/internal/ir/expr.go
+++ b/src/cmd/compile/internal/ir/expr.go
@@ -13,6 +13,8 @@ import (
 	"fmt"
 	"go/constant"
 	"go/token"
+	"hash/fnv"
+	"strconv"
 )
 
 // An Expr is a Node that can appear as an expression.
@@ -1183,17 +1185,21 @@ func MethodSymSuffix(recv *types.Type, msym *types.Sym, suffix string) *types.Sy
 		fmt.Fprintf(&b, "%-S", recv)
 	}
 
+	b.WriteString(".")
+	b.WriteString(msym.Name)
+
 	// A particular receiver type may have multiple non-exported
 	// methods with the same name. To disambiguate them, include a
 	// package qualifier for names that came from a different
 	// package than the receiver type.
 	if !types.IsExported(msym.Name) && msym.Pkg != rpkg {
-		b.WriteString(".")
-		b.WriteString(msym.Pkg.Prefix)
+		b.WriteString("+")
+
+		h := fnv.New32()
+		h.Write([]byte(msym.Pkg.Prefix))
+		b.WriteString(strconv.FormatUint(uint64(h.Sum32()), 16))
 	}
 
-	b.WriteString(".")
-	b.WriteString(msym.Name)
 	b.WriteString(suffix)
 	return rpkg.LookupBytes(b.Bytes())
 }
diff --git a/src/debug/gosym/pclntab_test.go b/src/debug/gosym/pclntab_test.go
index e380bb5ad73..cffe03d58a0 100644
--- a/src/debug/gosym/pclntab_test.go
+++ b/src/debug/gosym/pclntab_test.go
@@ -60,6 +60,7 @@ func endtest() {
 // skipIfNotELF skips the test if we are not running on an ELF system.
 // These tests open and examine the test binary, and use elf.Open to do so.
 func skipIfNotELF(t *testing.T) {
+	t.Helper()
 	switch runtime.GOOS {
 	case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris", "illumos":
 		// OK.
diff --git a/src/debug/gosym/symtab_test.go b/src/debug/gosym/symtab_test.go
index bb1f267a4df..510c110d16b 100644
--- a/src/debug/gosym/symtab_test.go
+++ b/src/debug/gosym/symtab_test.go
@@ -10,6 +10,7 @@ import (
 )
 
 func assertString(t *testing.T, dsc, out, tgt string) {
+	t.Helper()
 	if out != tgt {
 		t.Fatalf("Expected: %q Actual: %q for %s", tgt, out, dsc)
 	}
@@ -85,3 +86,28 @@ func TestIssue29551(t *testing.T) {
 		assertString(t, fmt.Sprintf("package of %q", tc.sym.Name), tc.sym.PackageName(), tc.pkgName)
 	}
 }
+
+func TestIssue66313(t *testing.T) {
+	tests := []struct {
+		sym          Sym
+		packageName  string
+		receiverName string
+		baseName     string
+	}{
+		{Sym{Name: "github.com/google/cel-go/parser/gen.(*CELLexer).reset+10c630b8"},
+			"github.com/google/cel-go/parser/gen",
+			"(*CELLexer)",
+			"reset+10c630b8",
+		},
+		{Sym{Name: "ariga.io/atlas/sql/sqlclient.(*Tx).grabConn+404a5a3"},
+			"ariga.io/atlas/sql/sqlclient",
+			"(*Tx)",
+			"grabConn+404a5a3"},
+	}
+
+	for _, tc := range tests {
+		assertString(t, fmt.Sprintf("package of %q", tc.sym.Name), tc.sym.PackageName(), tc.packageName)
+		assertString(t, fmt.Sprintf("receiver of %q", tc.sym.Name), tc.sym.ReceiverName(), tc.receiverName)
+		assertString(t, fmt.Sprintf("package of %q", tc.sym.Name), tc.sym.BaseName(), tc.baseName)
+	}
+}