Merge pull request #2025 from ArtemSarmini/issue-1971-basic_json-push_back

Fixes #1971 (memory leak in basic_json::push_back)
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Niels Lohmann 2020-04-10 13:19:14 +02:00 committed by GitHub
commit ea0a7c7b4f
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3 changed files with 44 additions and 6 deletions

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@ -4875,9 +4875,7 @@ class basic_json
// add element to array (move semantics) // add element to array (move semantics)
m_value.array->push_back(std::move(val)); m_value.array->push_back(std::move(val));
// invalidate object: mark it null so we do not call the destructor // if val is moved from, basic_json move constructor marks it null so we do not call the destructor
// cppcheck-suppress accessMoved
val.m_type = value_t::null;
} }
/*! /*!

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@ -19734,9 +19734,7 @@ class basic_json
// add element to array (move semantics) // add element to array (move semantics)
m_value.array->push_back(std::move(val)); m_value.array->push_back(std::move(val));
// invalidate object: mark it null so we do not call the destructor // if val is moved from, basic_json move constructor marks it null so we do not call the destructor
// cppcheck-suppress accessMoved
val.m_type = value_t::null;
} }
/*! /*!

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@ -234,3 +234,45 @@ TEST_CASE("controlled bad_alloc")
} }
} }
} }
namespace
{
template<class T>
struct allocator_no_forward : std::allocator<T>
{
allocator_no_forward() {}
template <class U>
allocator_no_forward(allocator_no_forward<U>) {}
template <class U>
struct rebind {
using other = allocator_no_forward<U>;
};
template <class... Args>
void construct(T* p, const Args&... args)
{
// force copy even if move is available
::new (static_cast<void*>(p)) T(args...);
}
};
}
TEST_CASE("bad my_allocator::construct")
{
SECTION("my_allocator::construct doesn't forward")
{
using bad_alloc_json = nlohmann::basic_json<std::map,
std::vector,
std::string,
bool,
std::int64_t,
std::uint64_t,
double,
allocator_no_forward>;
bad_alloc_json json;
json["test"] = bad_alloc_json::array_t();
json["test"].push_back("should not leak");
}
}