QLibrary.load() couldn't run out.

brucezcg

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QLibrary library("C:/Projects/build-HFDll-Desktop_Qt_5_12_3_MinGW_32_bit-Release/release/HFDll.dll");
if (!library.load())
qDebug() << library.errorString();

 ……

}

The program couldn't run out when executing: if (!library.load())

jsulm

@brucezcg said in QLibrary.load() couldn't run out.:

The program couldn't run out

What do you mean by that? load() returns false? If so what does errorString() return?

brucezcg

@jsulm Hi, when excute load(), will never return from the function. Seems like dead loop in load().[0_1561958421703_HFDll.dll](Uploading 100%)

jsulm

@brucezcg Did you try to disable the anti virus software?
Are you trying to load the lib in a 32bit application compiled with MinGW?
Did you try to run through debugger to see where it stops?

brucezcg

@jsulm I can't disable Antivirus because of no privilege,
I build this dll via Qt mingw 32 bit.
I couldn't see debug steps inside load().

jsulm

@brucezcg said in QLibrary.load() couldn't run out.:

I couldn't see debug steps inside load().

I mean the stack trace while running through debugger to see where it hangs.

brucezcg

@jsulm
1 ntdll!DbgBreakPoint 0x7799cbd1
2 ntdll!DbgUiRemoteBreakin 0x779d4329
3 ?? 0xbbf18d1f
4 ntdll!DbgUiIssueRemoteBreakin 0x779d42f0
5 KERNEL32!BaseThreadInitThunk 0x77098494
6 ntdll!RtlAreBitsSet 0x779941c8
7 ntdll!RtlAreBitsSet 0x77994198
8 ??

And The full backtrace:

Thread 4 (Thread 20388.0x46dc):
#0 0x7799cbd1 in ntdll!DbgBreakPoint () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#1 0x779d4329 in ntdll!DbgUiRemoteBreakin () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#2 0xbbf18d1f in ?? ()
No symbol table info available.
#3 0x779d42f0 in ntdll!DbgUiIssueRemoteBreakin () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#4 0x77098494 in KERNEL32!BaseThreadInitThunk () from C:\windows\System32\kernel32.dll
No symbol table info available.
#5 0x779941c8 in ntdll!RtlAreBitsSet () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#6 0x77994198 in ntdll!RtlAreBitsSet () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#7 0x00000000 in ?? ()
No symbol table info available.

Thread 3 (Thread 20388.0x524c):
#0 0x7799a94c in ntdll!ZwRemoveIoCompletion () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#1 0x773ffcca in KERNELBASE!GetQueuedCompletionStatus () from C:\windows\System32\KernelBase.dll
No symbol table info available.
#2 0x530fe8b5 in ?? () from C:\Program Files\McAfee\DLP\Agent\fcagpph32.dll
No symbol table info available.
#3 0x77098494 in KERNEL32!BaseThreadInitThunk () from C:\windows\System32\kernel32.dll
No symbol table info available.
#4 0x779941c8 in ntdll!RtlAreBitsSet () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#5 0x77994198 in ntdll!RtlAreBitsSet () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#6 0x00000000 in ?? ()
No symbol table info available.

Thread 2 (Thread 20388.0x44c0):
#0 0x7799a94c in ntdll!ZwRemoveIoCompletion () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#1 0x773ffcca in KERNELBASE!GetQueuedCompletionStatus () from C:\windows\System32\KernelBase.dll
No symbol table info available.
#2 0x530fe8b5 in ?? () from C:\Program Files\McAfee\DLP\Agent\fcagpph32.dll
No symbol table info available.
#3 0x77098494 in KERNEL32!BaseThreadInitThunk () from C:\windows\System32\kernel32.dll
No symbol table info available.
#4 0x779941c8 in ntdll!RtlAreBitsSet () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#5 0x77994198 in ntdll!RtlAreBitsSet () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#6 0x00000000 in ?? ()
No symbol table info available.

Thread 1 (Thread 20388.0x434):
#0 0x7799ab5c in ntdll!ZwMapViewOfSection () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#1 0x7796877f in ntdll!RtlAppendUnicodeStringToString () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#2 0x7796855d in ntdll!RtlAppendUnicodeStringToString () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#3 0x77965633 in ntdll!LdrGetDllHandleByMapping () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#4 0x0093d6c0 in ?? ()
No symbol table info available.
#5 0x77963fa6 in ntdll!TpAllocAlpcCompletionEx () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#6 0x77983945 in ntdll!TpSetTimerEx () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#7 0x7797c44e in ntdll!LdrGetDllHandleByName () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#8 0x0073f7e0 in ?? ()
No symbol table info available.
#9 0x7797af57 in ntdll!RtlEqualUnicodeString () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#10 0x7796a8db in ntdll!RtlCompareUnicodeStrings () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#11 0x77967d32 in ntdll!LdrLoadDll () from C:\windows\SYSTEM32\ntdll.dll
No symbol table info available.
#12 0x52e22e22 in ?? () from C:\Program Files\McAfee\DLP\Agent\fcagpph32.dll
No symbol table info available.
#13 0x71ab1000 in ?? ()
No symbol table info available.
#14 0x773e0631 in LoadLibraryW () from C:\windows\System32\KernelBase.dll
No symbol table info available.
#15 0x00b84342 in QLibraryPrivate::load_sys (this=0x93d768, this@entry=0x2bf96a70) at plugin\qlibrary_win.cpp:100
attempt = <error reading variable>
__for_range = <optimized out>
__for_begin = {i = 0x2bf96be4}
__for_end = <optimized out>
oldmode = <optimized out>
attempts = {<QList<QString>> = {<QListSpecialMethods<QString>> = {<No data fields>}, {p = {static shared_null = {ref = {atomic = {_q_value = {<std::__atomic_base<int>> = {static _S_alignment = 4, _M_i = -1}, static is_always_lock_free = true}}}, alloc = 0, begin = 0, end = 0, array = {0x0}}, d = 0x2bf96bb0}, d = 0x2bf96bb0}}, <No data fields>}
fsEntry = {m_filePath = {static null = {<No data fields>}, d = 0x2bf96930}, m_nativeFilePath = {static null = {<No data fields>}, d = 0xd458c0 QArrayData::shared_null}, m_lastSeparator = -2, m_firstDotInFileName = -2, m_lastDotInFileName = 0}
#16 0x00b81119 in QLibraryPrivate::load (this=0x2bf96a70) at plugin\qlibrary.cpp:553
ret = <optimized out>
PRETTY_FUNCTION = "bool QLibraryPrivate::load()"
#17 0x00b8146c in QLibrary::load (this=<optimized out>) at plugin\qlibrary.cpp:808
No locals.
#18 0x0040163b in qMain (argc=1, argv=argv@entry=0x8389a8) at ..\TestHFDll\main.cpp:11
a = {<QGuiApplication> = {<QCoreApplication> = {<QObject> = {_vptr.QObject = 0xa688968 <vtable for QApplication+8>, static staticMetaObject = {d = {superdata = 0x0, stringdata = 0xe24e00 <qt_meta_stringdata_QObject>, data = 0xe24ce0 <qt_meta_data_QObject>, static_metacall = 0xbb6112 <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x838a48}, static staticQtMetaObject = {d = {superdata = 0x0, stringdata = 0xe27d00 <qt_meta_stringdata_Qt>, data = 0xe24f00 <qt_meta_data_Qt>, static_metacall = 0x0, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0xe24cc4 QObject::staticMetaObject, stringdata = 0xe1d320 <qt_meta_stringdata_QCoreApplication>, data = 0xe1d200 <qt_meta_data_QCoreApplication>, static_metacall = 0xb8947a <QCoreApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, static self = 0x73fdd8}, static staticMetaObject = {d = {superdata = 0xe1d1e0 QCoreApplication::staticMetaObject, stringdata = 0x16374480 <qt_meta_stringdata_QGuiApplication>, data = 0x16374200 <qt_meta_data_QGuiApplication>, static_metacall = 0x15f46ea2 <QGuiApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0x1636a028 QGuiApplication::staticMetaObject, stringdata = 0xa5b7840 <qt_meta_stringdata_QApplication>, data = 0xa5b76c0 <qt_meta_data_QApplication>, static_metacall = 0xa1bcb44 <QApplication::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}}
library = {<QObject> = {_vptr.QObject = 0xf37eec <vtable for QLibrary+8>, static staticMetaObject = {d = {superdata = 0x0, stringdata = 0xe24e00 <qt_meta_stringdata_QObject>, data = 0xe24ce0 <qt_meta_data_QObject>, static_metacall = 0xbb6112 <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x2bf96a18}, static staticQtMetaObject = {d = {superdata = 0x0, stringdata = 0xe27d00 <qt_meta_stringdata_Qt>, data = 0xe24f00 <qt_meta_data_Qt>, static_metacall = 0x0, relatedMetaObjects = 0x0, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0xe24cc4 QObject::staticMetaObject, stringdata = 0xe1b2e0 <qt_meta_stringdata_QLibrary>, data = 0xe1b200 <qt_meta_data_QLibrary>, static_metacall = 0xb82298 <QLibrary::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d = 0x2bf96a70, did_load = true}
PRETTY_FUNCTION = "int qMain(int, char**)"
cwf = 0x77407420 <invalid_parameter+240>
w = {<QMainWindow> = {<QWidget> = {<QObject> = {_vptr.QObject = 0xfffffffe, static staticMetaObject = {d = {superdata = 0x0, stringdata = 0xe24e00 <qt_meta_stringdata_QObject>, data = 0xe24ce0 <qt_meta_data_QObject>, static_metacall = 0xbb6112 <QObject::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, d_ptr = {d = 0x73fe48}, static staticQtMetaObject = {d = {superdata = 0x0, stringdata = 0xe27d00 <qt_meta_stringdata_Qt>, data = 0xe24f00 <qt_meta_data_Qt>, static_metacall = 0x0, relatedMetaObjects = 0x0, extradata = 0x0}}}, <QPaintDevice> = {_vptr.QPaintDevice = 0x779a2bf0 <wcstombs+112>, painters = 34751, reserved = 0xfffffffe}, static staticMetaObject = {d = {superdata = 0xe24cc4 QObject::staticMetaObject, stringdata = 0xa5bd540 <qt_meta_stringdata_QWidget>, data = 0xa5bce60 <qt_meta_data_QWidget>, static_metacall = 0xa1fa28c <QWidget::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, data = 0x73fe10}, static staticMetaObject = {d = {superdata = 0xa5b40a4 QWidget::staticMetaObject, stringdata = 0xa5e5180 <qt_meta_stringdata_QMainWindow>, data = 0xa5e4f80 <qt_meta_data_QMainWindow>, static_metacall = 0xa309e02 <QMainWindow::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0xa5e4f74 <qt_meta_extradata_QMainWindow>, extradata = 0x0}}}, static staticMetaObject = {d = {superdata = 0xa5e4f5c QMainWindow::staticMetaObject, stringdata = 0x405210 <qt_meta_stringdata_MainWindow>, data = 0x405240 <qt_meta_data_MainWindow>, static_metacall = 0x401a18 <MainWindow::qt_static_metacall(QObject*, QMetaObject::Call, int, void**)>, relatedMetaObjects = 0x0, extradata = 0x0}}, ui = 0x77973812 <ntdll!RtlFreeHeap+546>}
#19 0x00402d80 in WinMain@16 () at qtmain_win.cpp:97
argc = 1
argvW = 0x91b5f8
argv = 0x8389a8
exitCode = <optimized out>
#20 0x004037cd in main ()
No symbol table info available.

jsulm

@brucezcg It really looks like McAfee is the problem here:

#12 0x52e22e22 in ?? () from C:\Program Files\McAfee\DLP\Agent\fcagpph32.dll
No symbol table info available.
#13 0x71ab1000 in ?? ()
No symbol table info available.
#14 0x773e0631 in LoadLibraryW () from C:\windows\System32\KernelBase.dll
No symbol table info available.
#15 0x00b84342 in QLibraryPrivate::load_sys (this=0x93d768, this@entry=0x2bf96a70) at plugin\qlibrary_win.cpp:100

brucezcg

@jsulm said in QLibrary.load() couldn't run out.:

@brucezcg It really looks like McAfee is the problem here:

#12 0x52e22e22 in ?? () from C:\Program Files\McAfee\DLP\Agent\fcagpph32.dll
No symbol table info available.
#13 0x71ab1000 in ?? ()
No symbol table info available.
#14 0x773e0631 in LoadLibraryW () from C:\windows\System32\KernelBase.dll
No symbol table info available.
#15 0x00b84342 in QLibraryPrivate::load_sys (this=0x93d768, this@entry=0x2bf96a70) at plugin\qlibrary_win.cpp:100

@jsulm Thanks for reply, McAfee is running on my OS and I couldn't stop it. Is there any workaround?

jsulm

@brucezcg Can't you ask your administrator to fix the problem with McAfee?