QPluginLoader instance always returns null

[meysam_hashemi]

mixed build mode perhaps? (release/debug)

No, Both are in debug!
The thing is, I did something exactly like this before with CMakeList.txt and Visual Studio but its not working with MinGW and QT Creator . I'm missing something but i have no idea what it is !!!

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Added after 18 minutes:

The following configs of library and plugin in `CMakeList.txt` work perfectly fine when i make the project with `Visual Studio`. (Made with CMake)

ADD_DEFINITIONS(${QT_DEFINITIONS})																						
    ADD_DEFINITIONS(-DUNICODE -D_UNICODE)																						
    ADD_DEFINITIONS(-DQT_PLUGIN)																				
    ADD_DEFINITIONS(-DQT_SHARED)																							
    ADD_DEFINITIONS(-DQT_DLL)																							
    ADD_DEFINITIONS(-DQT_LARGEFILE_SUPPORT)
    ADD_DEFINITIONS(-DQT_THREAD_SUPPORT)
 
    INCLUDE_DIRECTORIES(
    	${STANDARD_XFS_DIRECTORY}/INCLUDE
    )
 
    LINK_DIRECTORIES(
    	${STANDARD_XFS_DIRECTORY}
    	${STANDARD_XFS_DIRECTORY}/LIB
    )
 
    SET(XFS_LIBS
    	MSXFS
    	xfs_conf
    	SSIDLL
    )
 
    TARGET_LINK_LIBRARIES(Device-Manager 
    	${XFS_LIBS}
    )

ADD_DEFINITIONS(${QT_DEFINITIONS})																						
    ADD_DEFINITIONS(-DUNICODE -D_UNICODE)																						
    ADD_DEFINITIONS(-DQT_PLUGIN)																				
    ADD_DEFINITIONS(-DQT_SHARED)																							
    ADD_DEFINITIONS(-DQT_DLL)																							
    ADD_DEFINITIONS(-DQT_LARGEFILE_SUPPORT)
    ADD_DEFINITIONS(-DQT_THREAD_SUPPORT)

    INCLUDE_DIRECTORIES(
    	${STANDARD_XFS_DIRECTORY}/INCLUDE
    )
    
    LINK_DIRECTORIES(
    	${STANDARD_XFS_DIRECTORY}
    	${STANDARD_XFS_DIRECTORY}/LIB
    )
    
    SET(XFS_LIBS
    	MSXFS
    	xfs_conf
    	SSIDLL
    )
    
    TARGET_LINK_LIBRARIES(Device-Manager 
    	${XFS_LIBS}
    )

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And this is the configs of library and plugin in `.pro` file in `Qt Creator` with `MinGW` which is not working when i use the library.

QT  -= gui
    QT  += core sql
 
    TARGET = Device-Manager
    TEMPLATE = lib
    CONFIG += plugin
    CONFIG += c++11
 
    DEFINES += DEVICEMANAGER_LIBRARY
 
    INCLUDEPATH += $$(STANDARD_XFS_DIRECTORY)
    INCLUDEPATH += $$(STANDARD_XFS_DIRECTORY)/INCLUDE
    message(Include : $${INCLUDEPATH})
 
    LIBS += $$(STANDARD_XFS_DIRECTORY)/SSIDLL.lib
    LIBS += $$(STANDARD_XFS_DIRECTORY)/LIB/MSXFS.lib
    LIBS += $$(STANDARD_XFS_DIRECTORY)/LIB/xfs_conf.lib
    message(Lib : $${LIBS})

QT  -= gui
    QT  += core sql
    
    TARGET = Device-Manager
    TEMPLATE = lib
    CONFIG += plugin
    CONFIG += c++11
    
    DEFINES += DEVICEMANAGER_LIBRARY
    
    INCLUDEPATH += $$(STANDARD_XFS_DIRECTORY)
    INCLUDEPATH += $$(STANDARD_XFS_DIRECTORY)/INCLUDE
    message(Include : $${INCLUDEPATH})
    
    LIBS += $$(STANDARD_XFS_DIRECTORY)/SSIDLL.lib
    LIBS += $$(STANDARD_XFS_DIRECTORY)/LIB/MSXFS.lib
    LIBS += $$(STANDARD_XFS_DIRECTORY)/LIB/xfs_conf.lib
    message(Lib : $${LIBS})

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So i can say the code it self is fine and i'm definitely missing some configs in `.pro` file.

PS1: Plugin and the application that load the plugin, Both have `INCLUDEPATH` and `LIBS` of the library in their pro file.

PS2: The application and the plugin both are in debug mode

PS3: I dont get any compile error or linker error during compile.