Tests/RunCMake/ObjectLibrary/PreBuild.cmake - third_party/cmake - Git at Google

 add_library(A OBJECT a.c)
 add_custom_command(TARGET A PRE_BUILD
   COMMAND  ${CMAKE_COMMAND} -E echo "A pre-build"
   )
	add_library(A OBJECT a.c)
	add_custom_command(TARGET A PRE_BUILD
	COMMAND ${CMAKE_COMMAND} -E echo "A pre-build"
	)