where/what are static plugins?

[ht1]

Jacek, thanks,

Now myproject.pro is

TEMPLATE = app
TARGET = 
DEPENDPATH += .
INCLUDEPATH += .
CONFIG += staticlib
QTPLUGIN += qjpg \
                    qgif \
                    qmng

TEMPLATE = app
TARGET = 
DEPENDPATH += .
INCLUDEPATH += .
CONFIG += staticlib
QTPLUGIN += qjpg \
                    qgif \
                    qmng

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but I'm still getting "cannot find -lqjpg". I tried to compile with and without this is main.cpp:

Q_IMPORT_PLUGIN(qjpeg)
Q_IMPORT_PLUGIN(qgif)
Q_IMPORT_PLUGIN(qmng)

but still I get the "cannot find -lqjpg" error.

Is there anything else I could try to diagnose the problem? Thanks