diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 89bcacf2bba8..6e2e15c6cb6b 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -2492,8 +2492,8 @@ bool FloatExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
     return Visit(E->getRHS());
   }
 
-  // We can't evaluate pointer-to-member operations.
-  if (E->isPtrMemOp())
+  // We can't evaluate pointer-to-member operations or assignments.
+  if (E->isPtrMemOp() || E->isAssignmentOp())
     return false;
 
   // FIXME: Diagnostics?  I really don't understand how the warnings
diff --git a/clang/test/Sema/const-eval.c b/clang/test/Sema/const-eval.c
index bdb40ae54be3..6dcc6db76596 100644
--- a/clang/test/Sema/const-eval.c
+++ b/clang/test/Sema/const-eval.c
@@ -86,3 +86,5 @@ void rdar8875946() {
   double _Complex  P;
   float _Complex  P2 = 3.3f + P;
 }
+
+double d = (d = 0.0); // expected-error {{not a compile-time constant}}