Fix fallout of DSTifying PartialEq, PartialOrd, Eq, Ord

src/libregex/parse.rs

@@ -1020,6 +1020,8 @@ fn is_valid_cap(c: char) -> bool {
     || (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
 }
 
+// NOTE(stage0): remove function after a snapshot
+#[cfg(stage0)]
 fn find_class(classes: NamedClasses, name: &str) -> Option<Vec<(char, char)>> {
     match classes.binary_search(|&(s, _)| s.cmp(&name)) {
         slice::Found(i) => Some(classes[i].val1().to_vec()),
@@ -1027,6 +1029,14 @@ fn find_class(classes: NamedClasses, name: &str) -> Option<Vec<(char, char)>> {
     }
 }
 
+#[cfg(not(stage0))]  // NOTE(stage0): remove cfg after a snapshot
+fn find_class(classes: NamedClasses, name: &str) -> Option<Vec<(char, char)>> {
+    match classes.binary_search(|&(s, _)| s.cmp(name)) {
+        slice::Found(i) => Some(classes[i].val1().to_vec()),
+        slice::NotFound(_) => None,
+    }
+}
+
 type Class = &'static [(char, char)];
 type NamedClasses = &'static [(&'static str, &'static Class)];