Valgrind：使用atomic :: compare_exchange_weak时，条件跳转或移动取决于未初始化的值

我有一个任务来实现一个非常基本的无锁排序向量（仅具有插入和索引功能），并且一切正常，但是，valgrind表示我有条件地跳转/移动，具体取决于未初始化的值。我使用的是--track-origins = yes，但是我发现这并不是很有帮助。

这是我的索引运算符的代码：

int operator[](int pos) {
    Pair pdata_old = pdata.load();
    Pair pdata_new = pdata_old;

    // Increment ref count
    do {
        pdata_new = pdata_old;
        ++pdata_new.ref_count;
    } while (!pdata.compare_exchange_weak(pdata_old, pdata_new));

    // Get old data
    int ret_val = (*pdata_new.pointer)[pos];

    pdata_old = pdata.load();

    // Decrement ref count
    do {
        pdata_new = pdata_old;
        --pdata_new.ref_count;
        // assert(pdata_new.ref_count >= 0);
    } while (!pdata.compare_exchange_weak(pdata_old, pdata_new));

    return ret_val;
}

Pair只是一个包含vector *和int的结构，构造函数初始化其所有值。我找不到任何依赖未初始化数据的地方，至少仅通过查看我的代码即可。

这是相关的valgrind输出（第121行是在其上声明函数的行，第130和142是compare_exchange_weak（）行）：

==21299==
==21299== Thread 2:
==21299== Conditional jump or move depends on uninitialised value(s)
==21299==    at 0x10A5C2: LFSV::operator[](int) (lfsv.h:130)
==21299==    by 0x1099F4: read_position_0() (driver.cpp:27)
==21299==    by 0x10FCC6: void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) (invoke.h:60)
==21299==    by 0x10FC5C: std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) (invoke.h:95)
==21299==    by 0x10FC34: _ZNSt6thread8_InvokerISt5tupleIJPFvvEEEE9_M_invokeIJLm0EEEEDTclsr3stdE8__invokespcl10_S_declvalIXT_EEEEESt12_Index_tupleIJXspT_EEE (thread:234)
==21299==    by 0x10FC04: std::thread::_Invoker<std::tuple<void (*)()> >::operator()() (thread:243)
==21299==    by 0x10FAE8: std::thread::_State_impl<std::thread::_Invoker<std::tuple<void (*)()> > >::_M_run() (thread:186)
==21299==    by 0x50FAB9E: execute_native_thread_routine (thread.cc:83)
==21299==    by 0x593208B: start_thread (in /usr/lib/libpthread-2.26.so)
==21299==    by 0x5C3EE7E: clone (in /usr/lib/libc-2.26.so)
==21299==  Uninitialised value was created by a stack allocation
==21299==    at 0x10A520: LFSV::operator[](int) (lfsv.h:121)
==21299==
==21299== Conditional jump or move depends on uninitialised value(s)
==21299==    at 0x10A654: LFSV::operator[](int) (lfsv.h:142)
==21299==    by 0x1099F4: read_position_0() (driver.cpp:27)
==21299==    by 0x10FCC6: void std::__invoke_impl<void, void (*)()>(std::__invoke_other, void (*&&)()) (invoke.h:60)
==21299==    by 0x10FC5C: std::__invoke_result<void (*)()>::type std::__invoke<void (*)()>(void (*&&)()) (invoke.h:95)
==21299==    by 0x10FC34: _ZNSt6thread8_InvokerISt5tupleIJPFvvEEEE9_M_invokeIJLm0EEEEDTclsr3stdE8__invokespcl10_S_declvalIXT_EEEEESt12_Index_tupleIJXspT_EEE (thread:234)
==21299==    by 0x10FC04: std::thread::_Invoker<std::tuple<void (*)()> >::operator()() (thread:243)
==21299==    by 0x10FAE8: std::thread::_State_impl<std::thread::_Invoker<std::tuple<void (*)()> > >::_M_run() (thread:186)
==21299==    by 0x50FAB9E: execute_native_thread_routine (thread.cc:83)
==21299==    by 0x593208B: start_thread (in /usr/lib/libpthread-2.26.so)
==21299==    by 0x5C3EE7E: clone (in /usr/lib/libc-2.26.so)
==21299==  Uninitialised value was created by a stack allocation
==21299==    at 0x10A520: LFSV::operator[](int) (lfsv.h:121)
==21299==