Fix the keep_last warning when using system defaults.

[clalancette]

If the user creates SystemDefaultsQoS setting, they are explicitly asking for SystemDefaults. In that case, we should not warn, and just let the underlying RMW choose what it wants. Implement that here by passing a boolean parameter through that decides when we should print out the warning, and then skip printing that warning when SystemDefaultsQoS is created.

Signed-off-by: Chris Lalancette clalancette@openrobotics.org

[clalancette]

Note that this should fix ros2/rmw#341

[mjcarroll]

LGTM

[clalancette]

CI:

• Linux
• Linux-aarch64
• Windows

[mmattb]

Since this change went in I see my nav2_util build failing with:

--- stderr: nav2_util                                                                          
/usr/bin/ld: /opt/ros/rolling/lib/libbondcpp.so: undefined reference to `rclcpp::KeepLast::KeepLast(unsigned long)'
collect2: error: ld returned 1 exit status
gmake[2]: *** [test/CMakeFiles/test_string_utils.dir/build.make:266: test/test_string_utils] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:347: test/CMakeFiles/test_string_utils.dir/all] Error 2
gmake[1]: *** Waiting for unfinished jobs....

Not sure why the type conversion unsigned long -> size_t isn't working there? When I change it to something like this there is no problem.

diff --git a/rclcpp/include/rclcpp/qos.hpp b/rclcpp/include/rclcpp/qos.hpp
index 2ad49487..e3721510 100644
--- a/rclcpp/include/rclcpp/qos.hpp
+++ b/rclcpp/include/rclcpp/qos.hpp
@@ -99,7 +99,8 @@ struct RCLCPP_PUBLIC KeepAll : public rclcpp::QoSInitialization
 /// Use to initialize the QoS with the keep_last history setting and the given depth.
 struct RCLCPP_PUBLIC KeepLast : public rclcpp::QoSInitialization
 {
-  explicit KeepLast(size_t depth, bool print_depth_warning = true);
+  explicit KeepLast(size_t depth);
+  explicit KeepLast(size_t depth, bool print_depth_warning);
 };
 
 /// Encapsulation of Quality of Service settings.
diff --git a/rclcpp/src/rclcpp/qos.cpp b/rclcpp/src/rclcpp/qos.cpp
index 2453149a..1e61bf09 100644
--- a/rclcpp/src/rclcpp/qos.cpp
+++ b/rclcpp/src/rclcpp/qos.cpp
@@ -78,6 +78,11 @@ KeepAll::KeepAll()
 : QoSInitialization(RMW_QOS_POLICY_HISTORY_KEEP_ALL, 0)
 {}
 
+KeepLast::KeepLast(size_t depth)
+: QoSInitialization(RMW_QOS_POLICY_HISTORY_KEEP_LAST, depth, true)
+{
+}
+
 KeepLast::KeepLast(size_t depth, bool print_depth_warning)
 : QoSInitialization(RMW_QOS_POLICY_HISTORY_KEEP_LAST, depth, print_depth_warning)
 {

What is C++ doing here? This is Ubuntu 22.04 / ros2_rolling. Does libbondcpp need recompiling? Does the Ubuntu package for it need updating? Not sure the C++ details there.

[clalancette]

Almost certainly the problem is that you have a mixed workspace. That is, you have rclcpp in your overlay, and bondcpp in your underlay (/opt/ros/rolling). Since bondcpp hasn't been rebuilt against the new version of rclcpp, it has the wrong linkage.

Either you need to build everything from source here (including bondcpp), or you need to wait until we do an rclcpp release with this change in it (which will rebuild bondcpp underneath).