RIOTBASE=$(shell git rev-parse --show-toplevel)
  # Generate list of quoted absolute include paths. Evaluated in riot.doxyfile.
  export STRIP_FROM_INC_PATH_LIST=$(shell \
      git ls-tree -dr --full-tree --name-only HEAD core drivers sys |\
      grep '/include$$' |\
      sed 's/.*/\"$(subst /,\/,${RIOTBASE})\/\0\"/')
  
  # use lessc (http://lesscss.org/#using-less) for compiling CSS, alternatively
  # fall back to lesscpy (https://github.com/lesscpy/lesscpy)
  ifeq (,$(LESSC))
    ifneq (,$(shell command -v lessc 2>/dev/null))
      LESSC=lessc
    else ifneq (,$(shell command -v lesscpy 2>/dev/null))
      LESSC=lesscpy
    endif
  endif
  
  .PHONY: doc
  doc: html
  
  # by marking html as phony we force make to re-run Doxygen even if the directory exists.
  .PHONY: html
  html: src/css/riot.css src/changelog.md
  	( cat riot.doxyfile ; echo "GENERATE_HTML = yes" ) | doxygen -
  
  .PHONY: man
  man: src/changelog.md
  	( cat riot.doxyfile ; echo "GENERATE_MAN = yes" ) | doxygen -
  
  ifneq (,$(LESSC))
  src/css/riot.css: src/css/riot.less src/css/variables.less
  	@$(LESSC) $< $@
  
  src/css/variables.less: src/config.json
  	@grep "^\s*\"@" $< | sed -e 's/^\s*"//g' -e 's/":\s*"/: /g' \
  	  -e 's/",\?$$/;/g' -e 's/\\"/"/g' > $@
  endif
  
  src/changelog.md: src/changelog.md.tmp ../../release-notes.txt
  	@./generate-changelog.py $+ $@
  
  .PHONY:
  latex: src/changelog.md
  	( cat riot.doxyfile ; echo "GENERATE_LATEX= yes" ) | doxygen -
  
  clean:
  	-@rm -rf latex man html doxygen_objdb_*.tmp doxygen_entrydb_*.tmp src/changelog.md