QTPLUGIN += qjpeg doesnt let me compile

[locke]

Hi guys,

Im triying to save pictures as jpeg format. I do what trolls said in http://doc.trolltech.com/4.3/plugins...static-plugins
but when I include the line

QTPLUGIN     += qjpeg

QTPLUGIN     += qjpeg

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then, error: collect2: ld returned 1 exit status appears. What am I doing wrong?

thanks

[saa7_go]

Have you rebuild qjpeg plugin as static library?

[locke]

I have all the libraries in C:\Qt\2010.01\qt\plugins\imageformats. I have qjpeg4.dll, qjpeg4d.dll, qjpeg4.a, qjpeg4d.a

[saa7_go]

I have all the libraries in C:\Qt\2010.01\qt\plugins\imageformats. I have qjpeg4.dll, qjpeg4d.dll, qjpeg4.a, qjpeg4d.a

No, all files you mention are dynamic plugins. You must build the qjpeg plugin as a static plugin.

Quoting from http://doc.trolltech.com/4.3/plugins...static-plugins

It is also possible to create your own static plugins, by following these steps:

1. Add CONFIG += static to your plugin's .pro file.
2. Use the Q_IMPORT_PLUGIN() macro in your application.
3. Link your application with your plugin library using LIBS in the .pro file.

[locke]

I changed the things and now it works. But the way I did it is like I was creating a new plugind, not using an exsiting one. Istead of include the jpeg plugin like QTPLUGIN += qjpeg I needed to compile the plugins statically and then link the libraries using LIBS in my .pro file.

[dhjdhj]

I tried to do this as well (on a Macintosh) and I"m getting errors like the following:

Undefined symbols for architecture x86_64:
"qt_plugin_instance_qjpeg()", referenced from:
__static_initialization_and_destruction_0(int, int)in main.o

Anyone know how to fix this issue?


P.S. --- I looked in the libqjpeg.dylib with nm and noted that there is an entry called _qt_plugin_instance, but there is NOT an entry called _qt_plugin_instance_qjpeg, which is being defined by the Q_IMPORT_PLUGIN macro.