CMake: Don't use target_include_directories in CMake < 2.8.11

panda/src/express/CMakeLists.txt

@@ -145,10 +145,20 @@ set(P3EXPRESS_IGATEEXT
 
 composite_sources(p3express P3EXPRESS_SOURCES)
 
-add_library(p3express ${P3EXPRESS_SOURCES} ${P3EXPRESS_HEADERS})
+# p3express needs to include from p3interrogatedb for py_panda.h and extension.h
+if(CMAKE_VERSION VERSION_LESS 2.8.11)
+  get_target_property(interrogatedb_interface_dirs p3interrogatedb INTERFACE_INCLUDE_DIRECTORIES)
+  include_directories(${interrogatedb_interface_dirs})
+  add_library(p3express ${P3EXPRESS_SOURCES} ${P3EXPRESS_HEADERS})
+  set_target_properties(p3express PROPERTIES INTERFACE_INCLUDE_DIRECTORIES
+    "${interrogatedb_interface_dirs};${CMAKE_CURRENT_SOURCE_DIR}")
+else()
+  add_library(p3express ${P3EXPRESS_SOURCES} ${P3EXPRESS_HEADERS})
+  target_include_directories(p3express PUBLIC
+    $<TARGET_PROPERTY:p3interrogatedb,INTERFACE_INCLUDE_DIRECTORIES>)
+endif()
 target_link_libraries(p3express p3pandabase p3dtool p3prc p3dconfig
   ${_TAR_LIBRARY} ${_ZLIB_LIBRARY})
-target_include_directories(p3express PUBLIC $<TARGET_PROPERTY:p3interrogatedb,INTERFACE_INCLUDE_DIRECTORIES>)
 target_interrogate(p3express ALL EXTENSIONS ${P3EXPRESS_IGATEEXT})
 
 if(WIN32)