使用运行时API定位内存泄露

使用运行时API可以定位内存泄露，具体可以通过以下步骤实现：

1. 在 Xcode 中选择 Product -> Scheme -> Edit Scheme，然后在左侧选择 Run，接着在 Arguments Passed On Launch 中添加环境变量：MallocStackLoggingNoCompact，并将其值设为 1。

2. 在代码中添加以下代码：

#import <objc/runtime.h>

void checkMemoryLeak() {
    unsigned int count = 0;
    Class *classes = objc_copyClassList(&count);

    for (unsigned int i = 0; i < count; i++) {
        Class cls = classes[i];
        if (class_respondsToSelector(cls, @selector(doesNotRecognizeSelector:))) {
            // This class has no method implementations of its own.
            continue;
        }

        unsigned int methodCount = 0;
        Method *methods = class_copyMethodList(cls, &methodCount);
        for (unsigned int j = 0; j < methodCount; j++) {
            Method method = methods[j];
            SEL selector = method_getName(method);

            if (selector == @selector(alloc) || selector == @selector(new)) {
                // Skip alloc and new methods to avoid false positives.
                continue;
            }

            NSString *methodName = NSStringFromSelector(selector);
            if ([methodName hasPrefix:@"init"]) {
                // Skip init methods to avoid false positives.
                continue;
            }

            IMP imp = method_getImplementation(method);
            if (imp == NULL) {
                // Skip methods with no implementation.
                continue;
            }

            if (strstr(methodName.UTF8String, "copy") != NULL || strstr(methodName.UTF8String, "mutableCopy") != NULL) {
                // Skip copy and mutableCopy methods to avoid false positives.
                continue;
            }

            if (strstr(methodName.UTF8String, "retain") != NULL) {
                // Skip retain methods to avoid false positives.
                continue;
            }

            if (strstr(methodName.UTF8String, "release") != NULL || strstr(methodName.UTF8String, "autorelease") != NULL) {
                // Skip release and autorelease methods to avoid false positives.
                continue;
            }

            // Call the method with a nil argument to create an object without retaining it.
            ((id (*)(id, SEL, ...))method_invoke)(cls, selector, nil);
        }
        free(methods);
    }

    free(classes);
}

3. 在代码中调用 checkMemoryLeak 函数，这个函数会递归遍历所有类及其方法，并在不保留对象的情况下调用方法，从而创建对象并触发内存分配。如果有内存泄漏，可以通过 Instruments 工具捕获堆栈信息并进行分析。

需要注意的是，这个方法只是一种定位内存泄漏的手段，具体的问题还需要根据具体情况进行分析和解决。