Index: test/std/containers/sequences/vector.bool/copy.pass.cpp
===================================================================
--- test/std/containers/sequences/vector.bool/copy.pass.cpp
+++ test/std/containers/sequences/vector.bool/copy.pass.cpp
@@ -23,7 +23,7 @@
 void
 test(const C& x)
 {
-    unsigned s = x.size();
+    typename C::size_type s = x.size();
     C c(x);
     LIBCPP_ASSERT(c.__invariants());
     assert(c.size() == s);
Index: test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
===================================================================
--- test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
+++ test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
@@ -22,7 +22,7 @@
 void
 test(const C& x, const typename C::allocator_type& a)
 {
-    unsigned s = x.size();
+    typename C::size_type s = x.size();
     C c(x, a);
     LIBCPP_ASSERT(c.__invariants());
     assert(c.size() == s);
Index: test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
===================================================================
--- test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
+++ test/std/containers/sequences/vector/vector.cons/copy.pass.cpp
@@ -23,7 +23,7 @@
 void
 test(const C& x)
 {
-    unsigned s = x.size();
+    typename C::size_type s = x.size();
     C c(x);
     LIBCPP_ASSERT(c.__invariants());
     assert(c.size() == s);
Index: test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
===================================================================
--- test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
+++ test/std/containers/sequences/vector/vector.cons/copy_alloc.pass.cpp
@@ -23,7 +23,7 @@
 void
 test(const C& x, const typename C::allocator_type& a)
 {
-    unsigned s = x.size();
+    typename C::size_type s = x.size();
     C c(x, a);
     LIBCPP_ASSERT(c.__invariants());
     assert(c.size() == s);
Index: test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
===================================================================
--- test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
+++ test/std/strings/basic.string/string.cons/pointer_alloc.pass.cpp
@@ -15,6 +15,7 @@
 #include <stdexcept>
 #include <algorithm>
 #include <cassert>
+#include <cstddef>
 
 #include "test_macros.h"
 #include "test_allocator.h"
@@ -27,7 +28,7 @@
     typedef std::basic_string<charT, std::char_traits<charT>, test_allocator<charT> > S;
     typedef typename S::traits_type T;
     typedef typename S::allocator_type A;
-    unsigned n = T::length(s);
+    std::size_t n = T::length(s);
     S s2(s);
     LIBCPP_ASSERT(s2.__invariants());
     assert(s2.size() == n);
@@ -42,7 +43,7 @@
 {
     typedef std::basic_string<charT, std::char_traits<charT>, A> S;
     typedef typename S::traits_type T;
-    unsigned n = T::length(s);
+    std::size_t n = T::length(s);
     S s2(s, a);
     LIBCPP_ASSERT(s2.__invariants());
     assert(s2.size() == n);
Index: test/std/strings/basic.string/string.cons/substr.pass.cpp
===================================================================
--- test/std/strings/basic.string/string.cons/substr.pass.cpp
+++ test/std/strings/basic.string/string.cons/substr.pass.cpp
@@ -39,7 +39,7 @@
     {
         S s2(str, pos);
         LIBCPP_ASSERT(s2.__invariants());
-        unsigned rlen = str.size() - pos;
+        typename S::size_type rlen = str.size() - pos;
         assert(s2.size() == rlen);
         assert(T::compare(s2.data(), str.data() + pos, rlen) == 0);
         assert(s2.get_allocator() == A());
@@ -71,7 +71,7 @@
     {
         S s2(str, pos, n);
         LIBCPP_ASSERT(s2.__invariants());
-        unsigned rlen = std::min<unsigned>(str.size() - pos, n);
+        typename S::size_type rlen = std::min<typename S::size_type>(str.size() - pos, n);
         assert(s2.size() == rlen);
         assert(T::compare(s2.data(), str.data() + pos, rlen) == 0);
         assert(s2.get_allocator() == A());
@@ -104,7 +104,7 @@
     {
         S s2(str, pos, n, a);
         LIBCPP_ASSERT(s2.__invariants());
-        unsigned rlen = std::min<unsigned>(str.size() - pos, n);
+        typename S::size_type rlen = std::min<typename S::size_type>(str.size() - pos, n);
         assert(s2.size() == rlen);
         assert(T::compare(s2.data(), str.data() + pos, rlen) == 0);
         assert(s2.get_allocator() == a);
Index: test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
===================================================================
--- test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
+++ test/std/utilities/template.bitset/bitset.cons/ull_ctor.pass.cpp
@@ -22,7 +22,7 @@
     {
         TEST_CONSTEXPR std::bitset<N> v(0xAAAAAAAAAAAAAAAAULL);
         assert(v.size() == N);
-        unsigned M = std::min<std::size_t>(N, 64);
+        std::size_t M = std::min<std::size_t>(N, 64);
         for (std::size_t i = 0; i < M; ++i)
             assert(v[i] == ((i & 1) != 0));
         for (std::size_t i = M; i < N; ++i)