BBCLASSEXTEND="native nativesdk"

Question

After checked the official document, I still don’t understand this meaning in recipe.

BBCLASSEXTEND="native nativesdk"

Answer 1

BBCLASSEXTEND is a way for the named classes (in this case, native and nativesdk) to run over the recipe to alter them.

The native class makes a version of the recipe (with -native appended to the name) that builds for the build host instead of the build target, so you can execute the binaries during the build. The nativesdk class is similar but builds packages to be executed in the SDK.