ArchLinux build error - field has incomplete type ‘std::atomic<bool>’

[miko]

I get build error for v0.17:

$ make
[  3%] Building CXX object src/CMakeFiles/harmonySEQ.dir/Action.cpp.o
In file included from /tmp/harmonySEQ-0.17/src/Action.cpp:24:
/tmp/harmonySEQ-0.17/src/Engine.hpp:164:23: error: field ‘running’ has incomplete type ‘std::atomic<bool>’
  164 |     std::atomic<bool> running;
      |                       ^~~~~~~
In file included from /usr/include/c++/11.1.0/bits/shared_ptr_atomic.h:33,
                 from /usr/include/c++/11.1.0/memory:78,
                 from /tmp/harmonySEQ-0.17/src/Action.hpp:24,
                 from /tmp/harmonySEQ-0.17/src/Action.cpp:20:
/usr/include/c++/11.1.0/bits/atomic_base.h:155:12: note: declaration of ‘struct std::atomic<bool>’
  155 |     struct atomic;
      |            ^~~~~~
In file included from /tmp/harmonySEQ-0.17/src/Action.cpp:24:

The fix for above would be:

diff -Nur harmonySEQ-0.17/src/Engine.hpp harmonySEQ-0.17.new/src/Engine.hpp
--- harmonySEQ-0.17src/Engine.hpp	2020-03-04 14:48:23.000000000 +0100
+++ harmonySEQ-0.17.new/src/Engine.hpp	2021-09-22 09:50:36.781589576 +0200
@@ -22,6 +22,8 @@
 #ifndef MIDIDRIVER_H
 #define	MIDIDRIVER_H
 
+#include <atomic>
+#include <deque>
 #include <boost/signals2.hpp>
 namespace bs2 = boost::signals2;