dylib on Snow Leopard "file is not of required architecure"

Question

I have compiled opencv on snow leopard and it says it compiled correctly, however when I try to compile my sample program against it, I get output like:

g++ -o tm_scons template.o -L/opencv/opencv/build/lib -lcxcore -lcv -lcvaux -lhighgui -lml
ld: warning: in /opencv/opencv/build/lib/libcxcore.dylib, file is not of required architecture
ld: warning: in /opencv/opencv/build/lib/libcv.dylib, file is not of required architecture
ld: warning: in /opencv/opencv/build/lib/libcvaux.dylib, file is not of required architecture
ld: warning: in /opencv/opencv/build/lib/libhighgui.dylib, file is not of required architecture
ld: warning: in /opencv/opencv/build/lib/libml.dylib, file is not of required architecture

Any ideas on how to get past this?

Thanks!

Is this likely a problem with my compilation of OpenCV or of my app that is using it?

Answer 1

Compiling correctly does not mean compiling for whatever architecture you're trying to compile now. Most likely the library is compiled as 32-bit and you're compiling as 64-bit or vice-versa.

Answer 2

Most likely your program is compiled 64-bit (the default behavior on SnowLeopard) and the library is compiled 32-bit. Try adding the -m32 or -arch i386 flag to the compiler when you build your program and see if the link works.

Answer 3

As it turns out the magic was using -m32 and switching to the /usr/bin/g++-4.0 compiler.

Ugh....

Answer 4

Hi,

I think you get your problems solved with this tip or the provided binary here:

http://giesler.biz/~bjoern/blog/?p=183