diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.h b/clang/lib/AST/Interp/ByteCodeExprGen.h
--- a/clang/lib/AST/Interp/ByteCodeExprGen.h
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.h
@@ -71,6 +71,7 @@
   bool VisitCXXDefaultInitExpr(const CXXDefaultInitExpr *E);
   bool VisitCXXBoolLiteralExpr(const CXXBoolLiteralExpr *E);
   bool VisitCXXNullPtrLiteralExpr(const CXXNullPtrLiteralExpr *E);
+  bool VisitGNUNullExpr(const GNUNullExpr *E);
   bool VisitCXXThisExpr(const CXXThisExpr *E);
   bool VisitUnaryOperator(const UnaryOperator *E);
   bool VisitDeclRefExpr(const DeclRefExpr *E);
diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -1952,6 +1952,17 @@
   return this->emitNullPtr(E);
 }
 
+template <class Emitter>
+bool ByteCodeExprGen<Emitter>::VisitGNUNullExpr(const GNUNullExpr *E) {
+  if (DiscardResult)
+    return true;
+
+  assert(E->getType()->isIntegerType());
+
+  PrimType T = classifyPrim(E->getType());
+  return this->emitZero(T, E);
+}
+
 template <class Emitter>
 bool ByteCodeExprGen<Emitter>::VisitCXXThisExpr(const CXXThisExpr *E) {
   if (DiscardResult)
diff --git a/clang/test/AST/Interp/literals.cpp b/clang/test/AST/Interp/literals.cpp
--- a/clang/test/AST/Interp/literals.cpp
+++ b/clang/test/AST/Interp/literals.cpp
@@ -12,9 +12,13 @@
 static_assert(true, "");
 static_assert(false, ""); // expected-error{{failed}} ref-error{{failed}}
 static_assert(nullptr == nullptr, "");
+static_assert(__null == __null, "");
 static_assert(1 == 1, "");
 static_assert(1 == 3, ""); // expected-error{{failed}} ref-error{{failed}}
 
+constexpr void* v = nullptr;
+static_assert(__null == v, "");
+
 constexpr int number = 10;
 static_assert(number == 10, "");
 static_assert(number != 10, ""); // expected-error{{failed}} \
@@ -923,6 +927,7 @@
 
     (short)5;
     (bool)1;
+    __null;
 
     return 0;
   }