With this change only builds for NuttX which are very much flash size
constraint are optimized for size. All other builds (e.g. SITL,
Snapdragon, etc.) are left at the default for debugging or -O2 for the
usual use.
It makes more sense to set the optimization flags on a platform basis
instead of individually for each module. This allows for different
optimization options for SITL, NuttX, Snapdragon, etc.
This fixes a corner case where the first advertise/publish of a
vehicle_command_ack was missed. What happened was that the
orb_subscribe_multi was not called until the topic had been published
and therefore orb_exists was happy. This means that by the time
orb_subscribe_multi was finally called, the first vehicle_command_ack
was already history and not detected by orb_check.
This changed adds a flag to the MavlinkOrbSubscription which tells it to
subscribe to a topic from the beginning.
This reset the cruise speed which can be set by mission items/waypoints
to set a custom speed. Once, switched out of mission, it makes sense to
use the speed set by the param again.
The px4_os_add_flags defined in cmake/posix/px4_impl_posix.cmake did
add (threading) libraries to added_exe_linker_flags, which subsequently
end up in CMAKE_EXE_LINKER_FLAGS and then have no effect because those
flags are passed to the linker before any of the object files and static
libraries.
Those libraries are already added correctly in the corresponding
src/firmware/*/CMakeLists.txt files (for qurt, nuttx AND posix).
I left in the non-library linker flag '-pthread' for the bebop board,
although it seems very weird to me that this is needed (is it?).
If that is needed then it seems weird to link manually (that is,
src/firmware/*/CMakeLists.txt) with -lpthread.
For linux/g++ -pthread is added to the CXXFLAGS as it should be:
this causes the compiler to define _REENTRANT which is needed
for (the interface of) certain libraries to become thread-safe.
Offically one also can just pass -pthread to the linker, which then
causes the right libraries to be linked, but just linking with
-lpthread -lm -lrt works too.
I ran into this while adding support for libcwd, which explicitly
complains that _REENTRANT isn't defined when trying to link with
the thread-safe version of libcwd (-lcwd_r) and then tells you
to use -pthread.
Julian Oes
Lorenz Meier
Beat Küng
Daniel Agar
Dennis Shtatnov
David Sidrane
Carlo Wood