---
description: "Learn more about: Warning C26165"
title: Warning C26165
ms.date: 11/04/2016
f1_keywords: ["C26165"]
helpviewer_keywords: ["C26165"]
ms.assetid: a1d89bd6-08f3-4215-8a0c-b8ecfeb0cffc
---
# Warning C26165

> Possibly failing to release lock '*lock*' in function '*func*'.

Warning C26165 resembles warning [C26115](../code-quality/c26115.md) except that the confidence level is lower. For example, the function may contain annotation errors.

## Examples

The following code generates warning C26165.

```cpp
_Create_lock_level_(LockLevelOne);
_Create_lock_level_(LockLevelTwo);

struct LockLevelledStruct
{
    _Has_lock_level_(LockLevelOne) CRITICAL_SECTION a;
    _Has_lock_level_(LockLevelTwo) CRITICAL_SECTION b;
};

_Lock_level_order_(LockLevelOne, LockLevelTwo);

_Acquires_lock_(s->b) void GetLockFunc(LockLevelledStruct* s)
{
    EnterCriticalSection(&s->b);
}

void testLockLevelledStruct(LockLevelledStruct* s) // Warning C26165
{
    EnterCriticalSection(&s->a);
    GetLockFunc(s);
    LeaveCriticalSection(&s->a);
}
```

To correct this warning, change the previous example to the following.

```cpp
_Create_lock_level_(LockLevelOne);
_Create_lock_level_(LockLevelTwo);

struct LockLevelledStruct
{
    _Has_lock_level_(LockLevelOne) CRITICAL_SECTION a;
    _Has_lock_level_(LockLevelTwo) CRITICAL_SECTION b;
};

_Lock_level_order_(LockLevelOne, LockLevelTwo);

_Acquires_lock_(s->b) void GetLockFunc(LockLevelledStruct* s)
{
    EnterCriticalSection(&s->b);
}

_Releases_lock_(s->b) void ReleaseLockFunc(LockLevelledStruct* s)
{
    LeaveCriticalSection(&s->b);
}

void testLockLevelledStruct(LockLevelledStruct* s) // OK
{
    EnterCriticalSection(&s->a);
    GetLockFunc(s);
    ReleaseLockFunc(s);
    LeaveCriticalSection(&s->a);
}
```