Symptom A: Nav2/DWB fails with -Werror=maybe-uninitialized#

On the first colcon build after running bash install.sh in the repo root, 7 packages failed: nav2_constrained_smoother, nav2_smoother, nav2_planner, nav2_waypoint_follower, nav2_behaviors, dwb_critics and dwb_plugins.

The blocker was the toolchain treating warnings as errors, specifically -Werror=maybe-uninitialized.

Symptom B: partial rebuild fails with “Failed to find … package.sh”#

After the initial failure, trying to rebuild only Nav2 packages while their install prefixes were missing caused errors like:

• “Failed to find … package.sh”

Step 1: load the workspace environment#

1
cd ~/arena5_ws
2
source src/Arena/_meta/tools/source

Step 2 (optional): clean Nav2/DWB residues#

Do this if the install prefixes are missing, or if you want a clean forced rebuild for Nav2/DWB.

1
rm -rf build/nav2_* build/dwb_* install/nav2_* install/dwb_* log

Step 3 (only if needed): rebuild rosidl fundamentals#

If you see missing rosidl_cmake files (for example, it cannot find rosidl_generate_interfaces.cmake), clean rosidl and rebuild the rosidl baseline first:

1
rm -rf build/rosidl_* install/rosidl_* log
2

3
colcon build --symlink-install --event-handlers console_direct+ \
4
   --packages-select rosidl_cmake rosidl_generator_c rosidl_generator_cpp \
5
                            rosidl_typesupport_introspection_c rosidl_typesupport_introspection_cpp \
6
                            rosidl_typesupport_fastrtps_c rosidl_typesupport_fastrtps_cpp \
7
                            rosidl_generator_py rosidl_generator_tests \
8
   --cmake-args -DCMAKE_CXX_FLAGS="-Wno-error=maybe-uninitialized -Wno-error=uninitialized"

Step 4: rebuild Nav2 + DWB (allow warnings)#

1
colcon build --symlink-install --event-handlers console_direct+ \
2
   --packages-up-to nav2_behaviors nav2_constrained_smoother nav2_planner \
3
                           nav2_smoother nav2_waypoint_follower dwb_critics dwb_plugins \
4
   --cmake-args -DCMAKE_CXX_FLAGS="-Wno-error -Wno-error=maybe-uninitialized -Wno-error=uninitialized"