On Fri, May 17 2013, Austin Clements <amdragon@MIT.EDU> wrote: > Previously, we simply byte compiled each Elisp source file > independently. This is actually the wrong thing to do and can lead to > issues with macros and performance issues with substitutions because > 1) when the byte compiler encounters a (require 'x) form, it will load > x.elc in preference to x.el, even if x.el is newer, and as a result > may load old macro and substitution definitions and 2) if we update a > macro or substitution definition in one file, we currently won't > re-compile other files that depend on the file containing the > definition. > > This patch addresses these problems by computing make dependency rules > from the (require 'x) forms in the Elisp source files, which we inject > into make's dependency database. > --- > emacs/Makefile.local | 12 +++++++++ > emacs/make-deps.el | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 78 insertions(+) > create mode 100644 emacs/make-deps.el > > diff --git a/emacs/Makefile.local b/emacs/Makefile.local > index fb82247..456700a 100644 > --- a/emacs/Makefile.local > +++ b/emacs/Makefile.local > @@ -22,6 +22,18 @@ emacs_images := \ > > emacs_bytecode = $(emacs_sources:.el=.elc) > > +# Because of defmacro's and defsubst's, we have to account for load > +# dependencies between Elisp files when byte compiling. Otherwise, > +# the byte compiler may load an old .elc file when processing a > +# "require" or we may fail to rebuild a .elc that depended on a macro > +# from an updated file. > +$(dir)/.eldeps: $(dir)/Makefile.local $(dir)/make-deps.el $(emacs_sources) > + $(call quiet,EMACS) --directory emacs -batch -l make-deps.el \ > + -f batch-make-deps $(emacs_sources) > $@.tmp && \ > + (cmp -s $@.tmp $@ || mv $@.tmp $@) The last line above could be in format { cmp -s $@.tmp $@ || mv $@.tmp $@; } so that the expression is evaluated in current shell instead of a subshell. You may consider changing this if you add year to copyright line. Tomi > +-include $(dir)/.eldeps > +CLEAN+=$(dir)/.eldeps $(dir)/.eldeps.tmp > + > %.elc: %.el $(global_deps) > $(call quiet,EMACS) --directory emacs -batch -f batch-byte-compile $< >