https://issues.dlang.org/show_bug.cgi?id=13529

          Issue ID: 13529
           Summary: std.string.lastIndexOf matches wrong element
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: critical
          Priority: P1
         Component: Phobos
          Assignee: nobody@puremagic.com
          Reporter: rburners@gmail.com

unittest {
  ptrdiff_t idx = lastIndexOfH(to!dstring("Hällö Wörldö ö"),to!dstring("ö
öd"));
  assert(idx == -1); // fails
}

PR is in the works

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