Fix std::function allocator constructors in C++03.

The C++03 version of function tried to default construct the allocator
in the uses allocator constructors when no allocation was performed. These
constructors would fail to compile when used with allocators that had no
default constructor.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@239708 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/utilities/function.objects/func.wrap/func.wrap.func/func.wrap.func.con/alloc_F.pass.cpp

@@ -17,84 +17,90 @@
 #include <cassert>
 
 #include "min_allocator.h"
+#include "test_allocator.h"
+#include "count_new.hpp"
+#include "../function_types.h"
 
-class A
+class DummyClass {};
+
+template <class FuncType, class AllocType>
+void test_FunctionObject(AllocType& alloc)
 {
-    int data_[10];
-public:
-    static int count;
-
-    A()
+    assert(globalMemCounter.checkOutstandingNewEq(0));
     {
-        ++count;
-        for (int i = 0; i < 10; ++i)
-            data_[i] = i;
+    FunctionObject target;
+    assert(FunctionObject::count == 1);
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+    std::function<FuncType> f2(std::allocator_arg, alloc, target);
+    assert(FunctionObject::count == 2);
+    assert(globalMemCounter.checkOutstandingNewEq(1));
+    assert(f2.template target<FunctionObject>());
+    assert(f2.template target<FuncType>() == 0);
+    assert(f2.template target<FuncType*>() == 0);
     }
+    assert(FunctionObject::count == 0);
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+}
 
-    A(const A&) {++count;}
 
-    ~A() {--count;}
-
-    int operator()(int i) const
+template <class FuncType, class AllocType>
+void test_FreeFunction(AllocType& alloc)
+{
+    assert(globalMemCounter.checkOutstandingNewEq(0));
     {
-        for (int j = 0; j < 10; ++j)
-            i += data_[j];
-        return i;
+    FuncType* target = &FreeFunction;
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+    std::function<FuncType> f2(std::allocator_arg, alloc, target);
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+    assert(f2.template target<FuncType*>());
+    assert(*f2.template target<FuncType*>() == target);
+    assert(f2.template target<FuncType>() == 0);
+    assert(f2.template target<DummyClass>() == 0);
     }
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+}
 
-    int foo(int) const {return 1;}
-};
+template <class TargetType, class FuncType, class AllocType>
+void test_MemFunClass(AllocType& alloc)
+{
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+    {
+    TargetType target = &MemFunClass::foo;
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+    std::function<FuncType> f2(std::allocator_arg, alloc, target);
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+    assert(f2.template target<TargetType>());
+    assert(*f2.template target<TargetType>() == target);
+    assert(f2.template target<FuncType*>() == 0);
+    }
+    assert(globalMemCounter.checkOutstandingNewEq(0));
+}
 
-int A::count = 0;
+template <class Alloc>
+void test_for_alloc(Alloc& alloc) {
+    test_FunctionObject<int()>(alloc);
+    test_FunctionObject<int(int)>(alloc);
+    test_FunctionObject<int(int, int)>(alloc);
+    test_FunctionObject<int(int, int, int)>(alloc);
 
-int g(int) {return 0;}
+    test_FreeFunction<int()>(alloc);
+    test_FreeFunction<int(int)>(alloc);
+    test_FreeFunction<int(int, int)>(alloc);
+    test_FreeFunction<int(int, int, int)>(alloc);
 
-class Foo {
-public:
-  void bar(int k) { }
-};
+    test_MemFunClass<int(MemFunClass::*)() const, int(MemFunClass&)>(alloc);
+    test_MemFunClass<int(MemFunClass::*)(int) const, int(MemFunClass&, int)>(alloc);
+    test_MemFunClass<int(MemFunClass::*)(int, int) const, int(MemFunClass&, int, int)>(alloc);
+}
 
 int main()
 {
     {
-    std::function<int(int)> f(std::allocator_arg, bare_allocator<A>(), A());
-    assert(A::count == 1);
-    assert(f.target<A>());
-    assert(f.target<int(*)(int)>() == 0);
-    }
-    assert(A::count == 0);
-    {
-    std::function<int(int)> f(std::allocator_arg, bare_allocator<int(*)(int)>(), g);
-    assert(f.target<int(*)(int)>());
-    assert(f.target<A>() == 0);
+        bare_allocator<DummyClass> bare_alloc;
+        test_for_alloc(bare_alloc);
     }
     {
-    std::function<int(int)> f(std::allocator_arg, bare_allocator<int(*)(int)>(),
-                              (int (*)(int))0);
-    assert(!f);
-    assert(f.target<int(*)(int)>() == 0);
-    assert(f.target<A>() == 0);
-    }
-    {
-    std::function<int(const A*, int)> f(std::allocator_arg,
-                                        bare_allocator<int(A::*)(int)const>(),
-                                        &A::foo);
-    assert(f);
-    assert(f.target<int (A::*)(int) const>() != 0);
-    }
-#if __cplusplus >= 201103L
-    {
-    Foo f;
-    std::function<void(int)> fun = std::bind(&Foo::bar, &f, std::placeholders::_1);
-    fun(10);
-    }
-#endif
-    {
-    std::function<void(int)> fun(std::allocator_arg,
-                                 bare_allocator<int(*)(int)>(),
-                                 &g);
-    assert(fun);
-    assert(fun.target<int(*)(int)>() != 0);
-    fun(10);
+        non_default_test_allocator<DummyClass> non_default_alloc(42);
+        test_for_alloc(non_default_alloc);
     }
 }