--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libgo/misc/cgo/test/issue9026/issue9026.go	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,36 @@
+package issue9026
+
+// This file appears in its own package since the assertion tests the
+// per-package counter used to create fresh identifiers.
+
+/*
+typedef struct {} git_merge_file_input;
+
+typedef struct {} git_merge_file_options;
+
+void git_merge_file(
+        git_merge_file_input *in,
+        git_merge_file_options *opts) {}
+*/
+import "C"
+import (
+	"fmt"
+	"testing"
+)
+
+func Test(t *testing.T) {
+	var in C.git_merge_file_input
+	var opts *C.git_merge_file_options
+	C.git_merge_file(&in, opts)
+
+	// Test that the generated type names are deterministic.
+	// (Previously this would fail about 10% of the time.)
+	//
+	// Brittle: the assertion may fail spuriously when the algorithm
+	// changes, but should remain stable otherwise.
+	got := fmt.Sprintf("%T %T", in, opts)
+	want := "issue9026._Ctype_struct___0 *issue9026._Ctype_struct___1"
+	if got != want {
+		t.Errorf("Non-deterministic type names: got %s, want %s", got, want)
+	}
+}