GNU make dependency generation

November 2, 2015
make

Although I would normally use automake, recently I needed to write a Makefile by hand, so I went down the path of figuring out how to get gcc to generate dependency files as a side-effect of compilation:

# Build rule for compiling C++ with dependecy generation as a side-effect. The
# dependencies go into a .deps directory at the same level as the source file.
%.o: %.cpp
    @$(MKDIR) $(*D)/.deps
    $(CXX) $(CXXFLAGS) $(CPPFLAGS) -MP -MF $(*D)/.deps/$(*F).d -MMD -c $