1 files changed, 8 insertions, 0 deletions
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index a8d882a635e..8d9a1b23bb4 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -7217,6 +7217,14 @@ void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
           return;
 
         DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_precision);
+
+      }
+      // ... or possibly if we're increasing rank, too
+      else if (TargetBT->getKind() > SourceBT->getKind()) {
+        if (S.SourceMgr.isInSystemMacro(CC))
+          return;
+
+        DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_double_promotion);
       }
       return;
     }