Change the return type of emplace_[front|back] back to void when building with C++14 or before. Resolves PR31680.

llvm-svn: 292990

9 files changed, 165 insertions, 9 deletions

diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
index 77d822a0794..4142bc3694d 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
@@ -12,25 +12,35 @@
 // <queue>
 
 // template <class... Args> reference emplace(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
+
 
 #include <queue>
 #include <cassert>
 
+#include "test_macros.h"
+
 #include "../../../Emplaceable.h"
 
 int main()
 {
     typedef Emplaceable T;
     std::queue<Emplaceable> q;
+#if TEST_STD_VER > 14
     T& r1 = q.emplace(1, 2.5);
     assert(&r1 == &q.back());
     T& r2 = q.emplace(2, 3.5);
     assert(&r2 == &q.back());
     T& r3 = q.emplace(3, 4.5);
     assert(&r3 == &q.back());
+    assert(&r1 == &q.front());
+#else
+    q.emplace(1, 2.5);
+    q.emplace(2, 3.5);
+    q.emplace(3, 4.5);
+#endif
+
     assert(q.size() == 3);
     assert(q.front() == Emplaceable(1, 2.5));
     assert(q.back() == Emplaceable(3, 4.5));
-    assert(&r3 == &q.back());
-    assert(&r1 == &q.front());
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
index 71fe903b74a..8b19972eb32 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
@@ -12,22 +12,31 @@
 // <stack>
 
 // template <class... Args> reference emplace(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <stack>
 #include <cassert>
 
+#include "test_macros.h"
+
 #include "../../../Emplaceable.h"
 
 int main()
 {
     typedef Emplaceable T;
     std::stack<Emplaceable> q;
+#if TEST_STD_VER > 14
     T& r1 = q.emplace(1, 2.5);
     assert(&r1 == &q.top());
     T& r2 = q.emplace(2, 3.5);
     assert(&r2 == &q.top());
     T& r3 = q.emplace(3, 4.5);
     assert(&r3 == &q.top());
+#else
+    q.emplace(1, 2.5);
+    q.emplace(2, 3.5);
+    q.emplace(3, 4.5);
+#endif
     assert(q.size() == 3);
     assert(q.top() == Emplaceable(3, 4.5));
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
index e3a35362b18..13773fb1f5f 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
@@ -12,6 +12,7 @@
 // <deque>
 
 // template <class... Args> reference emplace_back(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <deque>
 #include <cstddef>
@@ -49,15 +50,21 @@ void
 test(C& c1)
 {
     typedef typename C::iterator I;
-    typedef typename C::reference Ref;
     std::size_t c1_osize = c1.size();
+#if TEST_STD_VER > 14
+    typedef typename C::reference Ref;
     Ref ref = c1.emplace_back(Emplaceable(1, 2.5));
+#else
+              c1.emplace_back(Emplaceable(1, 2.5));
+#endif
     assert(c1.size() == c1_osize + 1);
     assert(distance(c1.begin(), c1.end())
                == static_cast<std::ptrdiff_t>(c1.size()));
     I i = c1.end();
     assert(*--i == Emplaceable(1, 2.5));
+#if TEST_STD_VER > 14
     assert(&(*i) == &ref);
+#endif
 }
 
 template <class C>
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
index 26c700de725..4c272be48da 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
@@ -12,6 +12,7 @@
 // <deque>
 
 // template <class... Args> reference emplace_front(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <deque>
 #include <cstddef>
@@ -20,6 +21,7 @@
 #include "test_macros.h"
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
+#include "test_allocator.h"
 
 template <class C>
 C
@@ -48,15 +50,21 @@ void
 test(C& c1)
 {
     typedef typename C::iterator I;
-    typedef typename C::reference Ref;
     std::size_t c1_osize = c1.size();
+#if TEST_STD_VER > 14
+    typedef typename C::reference Ref;
     Ref res_ref = c1.emplace_front(Emplaceable(1, 2.5));
+#else
+                  c1.emplace_front(Emplaceable(1, 2.5));
+#endif
     assert(c1.size() == c1_osize + 1);
     assert(distance(c1.begin(), c1.end())
                == static_cast<std::ptrdiff_t>(c1.size()));
     I i = c1.begin();
     assert(*i == Emplaceable(1, 2.5));
+#if TEST_STD_VER > 14
     assert(&res_ref == &(*i));
+#endif
 }
 
 template <class C>
@@ -84,4 +92,15 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<Emplaceable, min_allocator<Emplaceable>> >(rng[i], rng[j]);
     }
+    {
+        std::deque<Tag_X, TaggingAllocator<Tag_X>> c;
+        c.emplace_front();
+        assert(c.size() == 1);
+        c.emplace_front(1, 2, 3);
+        assert(c.size() == 2);
+        c.emplace_front();
+        assert(c.size() == 3);
+        c.emplace_front(1, 2, 3);
+        assert(c.size() == 4);
+    }
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
index 589e71894b8..34591a1e196 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
@@ -12,10 +12,13 @@
 // <forward_list>
 
 // template <class... Args> reference emplace_front(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <forward_list>
 #include <cassert>
 
+#include "test_macros.h"
+
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
@@ -25,6 +28,7 @@ int main()
         typedef Emplaceable T;
         typedef std::forward_list<T> C;
         C c;
+#if TEST_STD_VER > 14
         T& r1 = c.emplace_front();
         assert(c.front() == Emplaceable());
         assert(&r1 == &c.front());
@@ -32,6 +36,13 @@ int main()
         T& r2 = c.emplace_front(1, 2.5);
         assert(c.front() == Emplaceable(1, 2.5));
         assert(&r2 == &c.front());
+#else
+        c.emplace_front();
+        assert(c.front() == Emplaceable());
+        assert(distance(c.begin(), c.end()) == 1);
+        c.emplace_front(1, 2.5);
+        assert(c.front() == Emplaceable(1, 2.5));
+#endif
         assert(*next(c.begin()) == Emplaceable());
         assert(distance(c.begin(), c.end()) == 2);
     }
@@ -39,6 +50,7 @@ int main()
         typedef Emplaceable T;
         typedef std::forward_list<T, min_allocator<T>> C;
         C c;
+#if TEST_STD_VER > 14
         T& r1 = c.emplace_front();
         assert(c.front() == Emplaceable());
         assert(&r1 == &c.front());
@@ -46,6 +58,13 @@ int main()
         T& r2 = c.emplace_front(1, 2.5);
         assert(c.front() == Emplaceable(1, 2.5));
         assert(&r2 == &c.front());
+#else
+        c.emplace_front();
+        assert(c.front() == Emplaceable());
+        assert(distance(c.begin(), c.end()) == 1);
+        c.emplace_front(1, 2.5);
+        assert(c.front() == Emplaceable(1, 2.5));
+#endif
         assert(*next(c.begin()) == Emplaceable());
         assert(distance(c.begin(), c.end()) == 2);
     }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
index 2aae2b9b09e..c63b0d8fbdb 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
@@ -12,10 +12,12 @@
 // <list>
 
 // template <class... Args> reference emplace_back(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <list>
 #include <cassert>
 
+#include "test_macros.h"
 #include "min_allocator.h"
 
 class A
@@ -37,6 +39,7 @@ int main()
 {
     {
     std::list<A> c;
+#if TEST_STD_VER > 14
     A& r1 = c.emplace_back(2, 3.5);
     assert(c.size() == 1);
     assert(&r1 == &c.back());
@@ -45,6 +48,14 @@ int main()
     A& r2 = c.emplace_back(3, 4.5);
     assert(c.size() == 2);
     assert(&r2 == &c.back());
+#else
+    c.emplace_back(2, 3.5);
+    assert(c.size() == 1);
+    assert(c.front().geti() == 2);
+    assert(c.front().getd() == 3.5);
+    c.emplace_back(3, 4.5);
+    assert(c.size() == 2);
+#endif
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
     assert(c.back().geti() == 3);
@@ -52,6 +63,7 @@ int main()
     }
     {
     std::list<A, min_allocator<A>> c;
+#if TEST_STD_VER > 14
     A& r1 = c.emplace_back(2, 3.5);
     assert(c.size() == 1);
     assert(&r1 == &c.back());
@@ -60,6 +72,14 @@ int main()
     A& r2 = c.emplace_back(3, 4.5);
     assert(c.size() == 2);
     assert(&r2 == &c.back());
+#else
+    c.emplace_back(2, 3.5);
+    assert(c.size() == 1);
+    assert(c.front().geti() == 2);
+    assert(c.front().getd() == 3.5);
+    c.emplace_back(3, 4.5);
+    assert(c.size() == 2);
+#endif
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
     assert(c.back().geti() == 3);
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
index 994dac258f8..a9be19e6f94 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
@@ -12,6 +12,7 @@
 // <list>
 
 // template <class... Args> reference emplace_front(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <list>
 #include <cassert>
@@ -37,6 +38,7 @@ int main()
 {
     {
     std::list<A> c;
+#if TEST_STD_VER > 14
     A& r1 = c.emplace_front(2, 3.5);
     assert(c.size() == 1);
     assert(&r1 == &c.front());
@@ -45,13 +47,23 @@ int main()
     A& r2 = c.emplace_front(3, 4.5);
     assert(c.size() == 2);
     assert(&r2 == &c.front());
+#else
+    c.emplace_front(2, 3.5);
+    assert(c.size() == 1);
+    assert(c.front().geti() == 2);
+    assert(c.front().getd() == 3.5);
+    c.emplace_front(3, 4.5);
+    assert(c.size() == 2);
+#endif
     assert(c.front().geti() == 3);
     assert(c.front().getd() == 4.5);
     assert(c.back().geti() == 2);
     assert(c.back().getd() == 3.5);
     }
+
     {
     std::list<A, min_allocator<A>> c;
+#if TEST_STD_VER > 14
     A& r1 = c.emplace_front(2, 3.5);
     assert(c.size() == 1);
     assert(&r1 == &c.front());
@@ -60,6 +72,14 @@ int main()
     A& r2 = c.emplace_front(3, 4.5);
     assert(c.size() == 2);
     assert(&r2 == &c.front());
+#else
+    c.emplace_front(2, 3.5);
+    assert(c.size() == 1);
+    assert(c.front().geti() == 2);
+    assert(c.front().getd() == 3.5);
+    c.emplace_front(3, 4.5);
+    assert(c.size() == 2);
+#endif
     assert(c.front().geti() == 3);
     assert(c.front().getd() == 4.5);
     assert(c.back().geti() == 2);
diff --git a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
index 24005bec82d..81a8ae47516 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
@@ -12,17 +12,20 @@
 //  vector.bool
 
 // template <class... Args> reference emplace_back(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <vector>
 #include <cassert>
+#include "test_macros.h"
 #include "min_allocator.h"
 
 int main()
 {
     {
         typedef std::vector<bool> C;
-        typedef C::reference Ref;
         C c;
+#if TEST_STD_VER > 14
+        typedef C::reference Ref;
         Ref r1 = c.emplace_back();
         assert(c.size() == 1);
         assert(c.front() == false);
@@ -36,19 +39,27 @@ int main()
         r2 = false;
         assert(c.back() == false);
         r2 = true;
-        Ref r3 = c.emplace_back(1 == 1);
+#else
+        c.emplace_back();
+        assert(c.size() == 1);
+        assert(c.front() == false);
+        c.emplace_back(true);
+        assert(c.size() == 2);
+        assert(c.front() == false);
+        assert(c.back() == true);
+#endif
+        c.emplace_back(1 == 1);
         assert(c.size() == 3);
         assert(c.front() == false);
         assert(c[1] == true);
         assert(c.back() == true);
-        r3 = false;
-        assert(c.back() == false);
     }
     {
         typedef std::vector<bool, min_allocator<bool>> C;
-        typedef C::reference Ref;
         C c;
 
+#if TEST_STD_VER > 14
+        typedef C::reference Ref;
         Ref r1 = c.emplace_back();
         assert(c.size() == 1);
         assert(c.front() == false);
@@ -62,6 +73,15 @@ int main()
         r2 = false;
         assert(c.back() == false);
         r2 = true;
+#else
+        c.emplace_back();
+        assert(c.size() == 1);
+        assert(c.front() == false);
+        c.emplace_back(true);
+        assert(c.size() == 2);
+        assert(c.front() == false);
+        assert(c.back() == true);
+#endif
         c.emplace_back(1 == 1);
         assert(c.size() == 3);
         assert(c.front() == false);
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
index 2fece8c78c7..f70c9b9abec 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
@@ -12,9 +12,11 @@
 // <vector>
 
 // template <class... Args> reference emplace_back(Args&&... args);
+// return type is 'reference' in C++17; 'void' before
 
 #include <vector>
 #include <cassert>
+#include "test_macros.h"
 #include "test_allocator.h"
 #include "min_allocator.h"
 #include "test_allocator.h"
@@ -56,6 +58,7 @@ int main()
 {
     {
         std::vector<A> c;
+#if TEST_STD_VER > 14
         A& r1 = c.emplace_back(2, 3.5);
         assert(c.size() == 1);
         assert(&r1 == &c.back());
@@ -65,6 +68,15 @@ int main()
         A& r2 = c.emplace_back(3, 4.5);
         assert(c.size() == 2);
         assert(&r2 == &c.back());
+#else
+        c.emplace_back(2, 3.5);
+        assert(c.size() == 1);
+        assert(c.front().geti() == 2);
+        assert(c.front().getd() == 3.5);
+        assert(is_contiguous_container_asan_correct(c));
+        c.emplace_back(3, 4.5);
+        assert(c.size() == 2);
+#endif
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(c.back().geti() == 3);
@@ -73,6 +85,7 @@ int main()
     }
     {
         std::vector<A, limited_allocator<A, 4> > c;
+#if TEST_STD_VER > 14
         A& r1 = c.emplace_back(2, 3.5);
         assert(c.size() == 1);
         assert(&r1 == &c.back());
@@ -82,6 +95,15 @@ int main()
         A& r2 = c.emplace_back(3, 4.5);
         assert(c.size() == 2);
         assert(&r2 == &c.back());
+#else
+        c.emplace_back(2, 3.5);
+        assert(c.size() == 1);
+        assert(c.front().geti() == 2);
+        assert(c.front().getd() == 3.5);
+        assert(is_contiguous_container_asan_correct(c));
+        c.emplace_back(3, 4.5);
+        assert(c.size() == 2);
+#endif
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(c.back().geti() == 3);
@@ -90,6 +112,7 @@ int main()
     }
     {
         std::vector<A, min_allocator<A>> c;
+#if TEST_STD_VER > 14
         A& r1 = c.emplace_back(2, 3.5);
         assert(c.size() == 1);
         assert(&r1 == &c.back());
@@ -99,6 +122,15 @@ int main()
         A& r2 = c.emplace_back(3, 4.5);
         assert(c.size() == 2);
         assert(&r2 == &c.back());
+#else
+        c.emplace_back(2, 3.5);
+        assert(c.size() == 1);
+        assert(c.front().geti() == 2);
+        assert(c.front().getd() == 3.5);
+        assert(is_contiguous_container_asan_correct(c));
+        c.emplace_back(3, 4.5);
+        assert(c.size() == 2);
+#endif
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(c.back().geti() == 3);