diff --git a/libcxx/include/forward_list b/libcxx/include/forward_list
--- a/libcxx/include/forward_list
+++ b/libcxx/include/forward_list
@@ -644,6 +644,11 @@
     typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
     typedef typename allocator_traits<allocator_type>::size_type       size_type;
     typedef typename allocator_traits<allocator_type>::difference_type difference_type;
+#if _LIBCPP_STD_VER > 17
+    typedef size_type __remove_return_type;
+#else
+    typedef void __remove_return_type;
+#endif
 
     typedef typename base::iterator       iterator;
     typedef typename base::const_iterator const_iterator;
@@ -819,11 +824,11 @@
     void splice_after(const_iterator __p, forward_list& __x, const_iterator __i);
     void splice_after(const_iterator __p, forward_list& __x,
                       const_iterator __f, const_iterator __l);
-    size_type remove(const value_type& __v);
-    template <class _Predicate> size_type remove_if(_Predicate __pred);
+    __remove_return_type remove(const value_type& __v);
+    template <class _Predicate> __remove_return_type remove_if(_Predicate __pred);
     _LIBCPP_INLINE_VISIBILITY
-    size_type unique() {return unique(__equal_to<value_type>());}
-    template <class _BinaryPredicate> size_type unique(_BinaryPredicate __binary_pred);
+    __remove_return_type unique() {return unique(__equal_to<value_type>());}
+    template <class _BinaryPredicate> __remove_return_type unique(_BinaryPredicate __binary_pred);
 #ifndef _LIBCPP_CXX03_LANG
     _LIBCPP_INLINE_VISIBILITY
     void merge(forward_list&& __x) {merge(__x, __less<value_type>());}
@@ -1496,7 +1501,7 @@
 }
 
 template <class _Tp, class _Alloc>
-typename forward_list<_Tp, _Alloc>::size_type
+typename forward_list<_Tp, _Alloc>::__remove_return_type
 forward_list<_Tp, _Alloc>::remove(const value_type& __v)
 {
     forward_list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
@@ -1518,13 +1523,17 @@
         else
             ++__i;
     }
-    
+
+#if _LIBCPP_STD_VER > 17
     return __count_removed;
+#else
+    (void)__count_removed;
+#endif
 }
 
 template <class _Tp, class _Alloc>
 template <class _Predicate>
-typename forward_list<_Tp, _Alloc>::size_type
+typename forward_list<_Tp, _Alloc>::__remove_return_type
 forward_list<_Tp, _Alloc>::remove_if(_Predicate __pred)
 {
     forward_list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
@@ -1546,13 +1555,17 @@
         else
             ++__i;
     }
-    
+
+#if _LIBCPP_STD_VER > 17
     return __count_removed;
+#else
+    (void)__count_removed;
+#endif
 }
 
 template <class _Tp, class _Alloc>
 template <class _BinaryPredicate>
-typename forward_list<_Tp, _Alloc>::size_type
+typename forward_list<_Tp, _Alloc>::__remove_return_type
 forward_list<_Tp, _Alloc>::unique(_BinaryPredicate __binary_pred)
 {
     forward_list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
@@ -1567,7 +1580,11 @@
         __i = __j;
     }
     
+#if _LIBCPP_STD_VER > 17
     return __count_removed;
+#else
+    (void)__count_removed;
+#endif
 }
 
 template <class _Tp, class _Alloc>
diff --git a/libcxx/include/list b/libcxx/include/list
--- a/libcxx/include/list
+++ b/libcxx/include/list
@@ -857,6 +857,11 @@
     typedef typename base::const_iterator            const_iterator;
     typedef _VSTD::reverse_iterator<iterator>         reverse_iterator;
     typedef _VSTD::reverse_iterator<const_iterator>   const_reverse_iterator;
+#if _LIBCPP_STD_VER > 17
+    typedef size_type __remove_return_type;
+#else
+    typedef void __remove_return_type;
+#endif
 
     _LIBCPP_INLINE_VISIBILITY
     list()
@@ -1070,12 +1075,12 @@
     void splice(const_iterator __p, list& __c, const_iterator __i);
     void splice(const_iterator __p, list& __c, const_iterator __f, const_iterator __l);
 
-    size_type remove(const value_type& __x);
-    template <class _Pred> size_type remove_if(_Pred __pred);
+    __remove_return_type remove(const value_type& __x);
+    template <class _Pred> __remove_return_type remove_if(_Pred __pred);
     _LIBCPP_INLINE_VISIBILITY
-    size_type unique() { return unique(__equal_to<value_type>()); }
+    __remove_return_type unique() { return unique(__equal_to<value_type>()); }
     template <class _BinaryPred>
-        size_type unique(_BinaryPred __binary_pred);
+        __remove_return_type unique(_BinaryPred __binary_pred);
     _LIBCPP_INLINE_VISIBILITY
     void merge(list& __c);
 #ifndef _LIBCPP_CXX03_LANG
@@ -2141,7 +2146,7 @@
 }
 
 template <class _Tp, class _Alloc>
-typename list<_Tp, _Alloc>::size_type
+typename list<_Tp, _Alloc>::__remove_return_type
 list<_Tp, _Alloc>::remove(const value_type& __x)
 {
     list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
@@ -2160,13 +2165,14 @@
         else
             ++__i;
     }
-
+#if _LIBCPP_STD_VER > 17
     return __deleted_nodes.size();
+#endif
 }
 
 template <class _Tp, class _Alloc>
 template <class _Pred>
-typename list<_Tp, _Alloc>::size_type
+typename list<_Tp, _Alloc>::__remove_return_type
 list<_Tp, _Alloc>::remove_if(_Pred __pred)
 {
     list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
@@ -2186,12 +2192,14 @@
             ++__i;
     }
 
+#if _LIBCPP_STD_VER > 17
     return __deleted_nodes.size();
+#endif
 }
 
 template <class _Tp, class _Alloc>
 template <class _BinaryPred>
-typename list<_Tp, _Alloc>::size_type
+typename list<_Tp, _Alloc>::__remove_return_type
 list<_Tp, _Alloc>::unique(_BinaryPred __binary_pred)
 {
     list<_Tp, _Alloc> __deleted_nodes(get_allocator()); // collect the nodes we're removing
@@ -2205,8 +2213,10 @@
             __i = __j;
             }
     }
-    
+
+#if _LIBCPP_STD_VER > 17
     return __deleted_nodes.size();
+#endif
 }
 
 template <class _Tp, class _Alloc>
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove.pass.cpp
@@ -27,6 +27,13 @@
     int *i_;
     };
 
+#if TEST_STD_VER > 17
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        assert((expr) == num_del);
+#else
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        expr;
+#endif
 
 int main(int, char**)
 {
@@ -37,7 +44,7 @@
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.remove(0) == 4);
+        ASSERT_CPP20_EQ(c1.remove(0), 4);
         assert(c1 == c2);
     }
     {
@@ -46,7 +53,7 @@
         const T t1[] = {0, 0, 0, 0};
         C c1(std::begin(t1), std::end(t1));
         C c2;
-        assert(c1.remove(0) == 4);
+        ASSERT_CPP20_EQ(c1.remove(0), 4);
         assert(c1 == c2);
     }
     {
@@ -56,7 +63,7 @@
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.remove(0) == 0);
+        ASSERT_CPP20_EQ(c1.remove(0), 0);
         assert(c1 == c2);
     }
     {
@@ -64,7 +71,7 @@
         typedef std::forward_list<T> C;
         C c1;
         C c2;
-        assert(c1.remove(0) == 0);
+        ASSERT_CPP20_EQ(c1.remove(0), 0);
         assert(c1 == c2);
     }
     {
@@ -74,7 +81,7 @@
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.remove(0) == 1);
+        ASSERT_CPP20_EQ(c1.remove(0), 1);
         assert(c1 == c2);
     }
     {  // LWG issue #526
@@ -84,7 +91,7 @@
     int t2[] = {   2,    3, 5, 8, 11};
     C c1(std::begin(t1), std::end(t1));
     C c2(std::begin(t2), std::end(t2));
-    assert(c1.remove(c1.front()) == 2);
+    ASSERT_CPP20_EQ(c1.remove(c1.front()), 2);
     assert(c1 == c2);
     }
     {
@@ -95,7 +102,7 @@
     C c;
     for(int *ip = std::end(t1); ip != std::begin(t1);)
         c.push_front(S(*--ip));
-    assert(c.remove(c.front()) == 3);
+    ASSERT_CPP20_EQ(c.remove(c.front()), 3);
     C::const_iterator it = c.begin();
     for(int *ip = std::begin(t2); ip != std::end(t2); ++ip, ++it) {
         assert ( it != c.end());
@@ -111,7 +118,7 @@
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.remove(0) == 4);
+        ASSERT_CPP20_EQ(c1.remove(0), 4);
         assert(c1 == c2);
     }
     {
@@ -120,7 +127,7 @@
         const T t1[] = {0, 0, 0, 0};
         C c1(std::begin(t1), std::end(t1));
         C c2;
-        assert(c1.remove(0) == 4);
+        ASSERT_CPP20_EQ(c1.remove(0), 4);
         assert(c1 == c2);
     }
     {
@@ -130,7 +137,7 @@
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.remove(0) == 0);
+        ASSERT_CPP20_EQ(c1.remove(0), 0);
         assert(c1 == c2);
     }
     {
@@ -138,7 +145,7 @@
         typedef std::forward_list<T, min_allocator<T>> C;
         C c1;
         C c2;
-        assert(c1.remove(0) == 0);
+        ASSERT_CPP20_EQ(c1.remove(0), 0);
         assert(c1 == c2);
     }
     {
@@ -148,7 +155,7 @@
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.remove(0) == 1);
+        ASSERT_CPP20_EQ(c1.remove(0), 1);
         assert(c1 == c2);
     }
 #endif
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp
@@ -19,6 +19,13 @@
 #include "min_allocator.h"
 #include "counting_predicates.hpp"
 
+#if TEST_STD_VER > 17
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        assert((expr) == num_del);
+#else
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        expr;
+#endif
 
 bool g(int i)
 {
@@ -45,7 +52,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 4);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 4);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -57,7 +64,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2;
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 4);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 4);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -70,7 +77,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 0);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 0);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -81,7 +88,7 @@
         C c1;
         C c2;
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 0);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 0);
         assert(c1 == c2);
         assert(cp.count() == 0);
     }
@@ -94,7 +101,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 1);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 1);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -123,7 +130,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 4);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 4);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -135,7 +142,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2;
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 4);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 4);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -148,7 +155,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 0);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 0);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
@@ -159,7 +166,7 @@
         C c1;
         C c2;
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 0);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 0);
         assert(c1 == c2);
         assert(cp.count() == 0);
     }
@@ -172,7 +179,7 @@
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
         Predicate cp(g);
-        assert(c1.remove_if(std::ref(cp)) == 1);
+        ASSERT_CPP20_EQ(c1.remove_if(std::ref(cp)), 1);
         assert(c1 == c2);
         assert(cp.count() == static_cast<std::size_t>(std::distance(std::begin(t1), std::end(t1))));
     }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.ops/unique.pass.cpp
@@ -17,6 +17,14 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
+#if TEST_STD_VER > 17
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        assert((expr) == num_del);
+#else
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        expr;
+#endif
+
 int main(int, char**)
 {
     {
@@ -26,7 +34,7 @@
         const T t2[] = {0, 5, 0, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 3);
+        ASSERT_CPP20_EQ(c1.unique(), 3);
         assert(c1 == c2);
     }
     {
@@ -36,7 +44,7 @@
         const T t2[] = {0};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 3);
+        ASSERT_CPP20_EQ(c1.unique(), 3);
         assert(c1 == c2);
     }
     {
@@ -46,7 +54,7 @@
         const T t2[] = {5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 2);
+        ASSERT_CPP20_EQ(c1.unique(), 2); 
         assert(c1 == c2);
     }
     {
@@ -54,7 +62,7 @@
         typedef std::forward_list<T> C;
         C c1;
         C c2;
-        assert(c1.unique() == 0);
+        ASSERT_CPP20_EQ(c1.unique(), 0);
         assert(c1 == c2);
     }
     {
@@ -64,7 +72,7 @@
         const T t2[] = {5, 0};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 2);
+        ASSERT_CPP20_EQ(c1.unique(), 2);
         assert(c1 == c2);
     }
 #if TEST_STD_VER >= 11
@@ -75,7 +83,7 @@
         const T t2[] = {0, 5, 0, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 3);
+        ASSERT_CPP20_EQ(c1.unique(), 3);
         assert(c1 == c2);
     }
     {
@@ -85,7 +93,7 @@
         const T t2[] = {0};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 3);
+        ASSERT_CPP20_EQ(c1.unique(), 3);
         assert(c1 == c2);
     }
     {
@@ -95,7 +103,7 @@
         const T t2[] = {5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 2);
+        ASSERT_CPP20_EQ(c1.unique(), 2);
         assert(c1 == c2);
     }
     {
@@ -103,7 +111,7 @@
         typedef std::forward_list<T, min_allocator<T>> C;
         C c1;
         C c2;
-        assert(c1.unique() == 0);
+        ASSERT_CPP20_EQ(c1.unique(), 0);
         assert(c1 == c2);
     }
     {
@@ -113,7 +121,7 @@
         const T t2[] = {5, 0};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        assert(c1.unique() == 2);
+        ASSERT_CPP20_EQ(c1.unique(), 2);
         assert(c1 == c2);
     }
 #endif
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp
--- a/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/remove.pass.cpp
@@ -16,6 +16,14 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
+#if TEST_STD_VER > 17
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        assert((expr) == num_del);
+#else
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        expr;
+#endif
+
 struct S {
   S(int i) : i_(new int(i)) {}
   S(const S &rhs) : i_(new int(*rhs.i_)) {}
@@ -37,7 +45,7 @@
     int a1[] = {1, 2, 3, 4};
     int a2[] = {1, 2, 4};
     std::list<int> c(a1, a1 + 4);
-    assert(c.remove(3) == 1);
+    ASSERT_CPP20_EQ(c.remove(3), 1);
     assert(c == std::list<int>(a2, a2 + 3));
   }
   { // LWG issue #526
@@ -53,7 +61,7 @@
     std::list<S> c;
     for (int *ip = a1; ip < a1 + 8; ++ip)
       c.push_back(S(*ip));
-    assert(c.remove(c.front()) == 3);
+    ASSERT_CPP20_EQ(c.remove(c.front()), 3);
     std::list<S>::const_iterator it = c.begin();
     for (int *ip = a2; ip < a2 + 5; ++ip, ++it) {
       assert(it != c.end());
@@ -67,7 +75,7 @@
     int a1[] = {1, 2, 3, 4};
     int a2[] = {1, 2, 4};
     List c(a1, a1 + 4, Alloc::create());
-      assert(c.remove(3) == 1);
+    ASSERT_CPP20_EQ(c.remove(3), 1);
     assert(c == List(a2, a2 + 3, Alloc::create()));
   }
 #if TEST_STD_VER >= 11
@@ -75,7 +83,7 @@
     int a1[] = {1, 2, 3, 4};
     int a2[] = {1, 2, 4};
     std::list<int, min_allocator<int>> c(a1, a1 + 4);
-    assert(c.remove(3) == 1);
+    ASSERT_CPP20_EQ(c.remove(3), 1);
     assert((c == std::list<int, min_allocator<int>>(a2, a2 + 3)));
   }
 #endif
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp
--- a/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/remove_if.pass.cpp
@@ -18,6 +18,14 @@
 #include "min_allocator.h"
 #include "counting_predicates.hpp"
 
+#if TEST_STD_VER > 17
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        assert((expr) == num_del);
+#else
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        expr;
+#endif
+
 bool even(int i)
 {
     return i % 2 == 0;
@@ -46,7 +54,7 @@
     int a2[] = {3, 4};
     std::list<int> c(a1, a1+4);
     Predicate cp(g);
-    assert(c.remove_if(std::ref(cp)) == 2);
+    ASSERT_CPP20_EQ(c.remove_if(std::ref(cp)), 2);
     assert(c == std::list<int>(a2, a2+2));
     assert(cp.count() == 4);
     }
@@ -55,7 +63,7 @@
     int a2[] = {1, 3};
     std::list<int> c(a1, a1+4);
     Predicate cp(even);
-    assert(c.remove_if(std::ref(cp)) == 2);
+    ASSERT_CPP20_EQ(c.remove_if(std::ref(cp)), 2);
     assert(c == std::list<int>(a2, a2+2));
     assert(cp.count() == 4);
     }
@@ -78,7 +86,7 @@
     int a2[] = {3, 4};
     std::list<int, min_allocator<int>> c(a1, a1+4);
     Predicate cp(g);
-    assert(c.remove_if(std::ref(cp)) == 2);
+    ASSERT_CPP20_EQ(c.remove_if(std::ref(cp)), 2);
     assert((c == std::list<int, min_allocator<int>>(a2, a2+2)));
     assert(cp.count() == 4);
     }
diff --git a/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp b/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp
--- a/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.ops/unique.pass.cpp
@@ -16,13 +16,21 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
+#if TEST_STD_VER > 17
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        assert((expr) == num_del);
+#else
+  #define ASSERT_CPP20_EQ(expr, num_del) \
+        expr;
+#endif
+
 int main(int, char**)
 {
     {
     int a1[] = {2, 1, 1, 4, 4, 4, 4, 3, 3};
     int a2[] = {2, 1, 4, 3};
     std::list<int> c(a1, a1+sizeof(a1)/sizeof(a1[0]));
-    assert(c.unique() == 5);
+    ASSERT_CPP20_EQ(c.unique(), 5);
     assert(c == std::list<int>(a2, a2+4));
     }
 #if TEST_STD_VER >= 11
@@ -30,7 +38,7 @@
     int a1[] = {2, 1, 1, 4, 4, 4, 4, 3, 3};
     int a2[] = {2, 1, 4, 3};
     std::list<int, min_allocator<int>> c(a1, a1+sizeof(a1)/sizeof(a1[0]));
-    assert(c.unique() == 5);
+    ASSERT_CPP20_EQ(c.unique(), 5);
     assert((c == std::list<int, min_allocator<int>>(a2, a2+4)));
     }
 #endif