On Friday 2021-08-27 23:09, Jeremy Sowden wrote: >Running autogen.sh gives the following output when it gets to >doxygen/Makefile.am: > > doxygen/Makefile.am:3: warning: shell find $(top_srcdir: non-POSIX variable name > doxygen/Makefile.am:3: (probably a GNU make extension) > >Automake doesn't understand the GNU make $(shell ...) [...] Or, third option, ditch the wildcarding and just name the sources. If going for a single Makefile (ditching recursive make), that will also be beneficial for parallel building, and the repo is not too large for such undertaking to be infeasible.