1 files changed, 16 insertions, 0 deletions
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 65d23418631..3619834fce6 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -7394,6 +7394,22 @@ Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS,
         return IncompatibleVectors;
       }
     }
+
+    // When the RHS comes from another lax conversion (e.g. binops between
+    // scalars and vectors) the result is canonicalized as a vector. When the
+    // LHS is also a vector, the lax is allowed by the condition above. Handle
+    // the case where LHS is a scalar.
+    if (LHSType->isScalarType()) {
+      const VectorType *VecType = RHSType->getAs<VectorType>();
+      if (VecType && VecType->getNumElements() == 1 &&
+          isLaxVectorConversion(RHSType, LHSType)) {
+        ExprResult *VecExpr = &RHS;
+        *VecExpr = ImpCastExprToType(VecExpr->get(), LHSType, CK_BitCast);
+        Kind = CK_BitCast;
+        return Compatible;
+      }
+    }
+
     return Incompatible;
   }