1 files changed, 3 insertions, 4 deletions
diff --git a/clang/lib/Basic/Diagnostic.cpp b/clang/lib/Basic/Diagnostic.cpp
index c95681496a8..c82f74413ec 100644
--- a/clang/lib/Basic/Diagnostic.cpp
+++ b/clang/lib/Basic/Diagnostic.cpp
@@ -205,10 +205,9 @@ DiagnosticsEngine::DiagStateMap::lookup(SourceManager &SrcMgr,
 
 DiagnosticsEngine::DiagState *
 DiagnosticsEngine::DiagStateMap::File::lookup(unsigned Offset) const {
-  auto OnePastIt = std::upper_bound(
-      StateTransitions.begin(), StateTransitions.end(), Offset,
-      [](unsigned Offset, const DiagStatePoint &P) {
-        return Offset < P.Offset;
+  auto OnePastIt =
+      llvm::partition_point(StateTransitions, [=](const DiagStatePoint &P) {
+        return P.Offset <= Offset;
       });
   assert(OnePastIt != StateTransitions.begin() && "missing initial state");
   return OnePastIt[-1].State;