perf: deep packages are swarmed with duplicated libraries in ament_target_dependencies() #541
Description
Here is a cmake trace when building the autoware_behavior_path_planner:
Most Autoware packages rely on ament_auto_* macros to build and export libraries.
This feels a bit like #442, except it's no more ament_libraries_deduplicate's fault (it is rather pretty fast):
By adding some log messages here and there, I have found that this package is swarmed by duplicated libraries:
diff --git a/ament_cmake_target_dependencies/cmake/ament_target_dependencies.cmake b/ament_cmake_target_dependencies/cmake/ament_target_dependencies.cmake
index 50bb69c..e18e94f 100644
--- a/ament_cmake_target_dependencies/cmake/ament_target_dependencies.cmake
+++ b/ament_cmake_target_dependencies/cmake/ament_target_dependencies.cmake
@@ -110,6 +110,10 @@ function(ament_target_dependencies target)
# otherwise use the classic CMake variables
list_append_unique(definitions ${${package_name}_DEFINITIONS})
list_append_unique(include_dirs ${${package_name}_INCLUDE_DIRS})
+ message(STATUS "####################################")
+ message(STATUS "package: ${package_name}")
+ message(STATUS "libraries: ${${package_name}_LIBRARIES}")
+ message(STATUS "####################################")
foreach(library ${${package_name}_LIBRARIES})
if(NOT "${${package_name}_LIBRARY_DIRS}" STREQUAL "")
if(NOT IS_ABSOLUTE ${library} OR NOT EXISTS ${library})Here is just the log output from a single dependency of autoware_behavior_path_planner:
output.txt
There are 8410 libraries, but only 669 of them are unique.
So the cmake processing is slow simply because ament_target_dependencies loops over way too many duplicated items.
It could be a mistake from Autoware's use of ament_auto_* macros, but it feels strange to find so many duplicates. Any idea?