--- /dev/null
+package pkg
+
+import "strings"
+
+func fn() {
+ println(strings.Trim("\x80test\xff", "\xff")) // want `is not a valid UTF-8 encoded string`
+ println(strings.Trim("foo", "bar"))
+
+ s := "\xff"
+ if true {
+ s = ""
+ }
+ println(strings.Trim("", s))
+}