Hello,

in my experience it was also necessary to specify things like CMAKE_FIND_ROOT_PATH, otherwise cmake didn't find libraries in the poky SDK sysroot (also see cmake cross-compiling documentation). Here's what I've been using for cross-compiling with a poky SDK installed to /opt/poky/<version>:

source /opt/poky/<version>/environment-setup-*

cmake <srcdir> \
  -DCMAKE_SYSTEM_NAME=Linux \
  -DCMAKE_SYSTEM_VERSION=1 \
  -DCMAKE_FIND_ROOT_PATH=/opt/poky/<version>/sysroots/<target> \
  -DCMAKE_FIND_ROOT_PATH_MODE_PROGRAM=NEVER \
  -DCMAKE_FIND_ROOT_PATH_MODE_LIBRARY=ONLY \
  -DCMAKE_FIND_ROOT_PATH_MODE_INCLUDE=ONLY

Another important detail is that the poky SDK must include all the *-dev packages needed.

Regards,

Daniel