* Makefile.in ${SUBDIR}: Pass additional BOOTSTRAPEMACS argument.

* Makefile.in (${lisp} ${SOME_MACHINE_LISP}, ../lisp/loaddefs.el):
Use $(BOOTSTRAPEMACS) rather than witness-emacs.
(bootstrap-emacs${EXEEXT}): Merge witness-emacs into it.
(witness-emacs): Remove.
(lisp, shortlisp): Move loaddefs.el earlier.
(mostlyclean): Forget about witness-emacs.
* Makefile.in (COMPILE_FIRST): Trim down and add autoload.el.

6 files changed, 61 insertions, 34 deletions

diff --git a/ChangeLog b/ChangeLog
index bf00c773970..a3277e82cbb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2008-06-22  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * Makefile.in ${SUBDIR}: Pass additional BOOTSTRAPEMACS argument.
+
 2008-06-22  Glenn Morris  <rgm@gnu.org>
 
         * Makefile.in (top_bootclean): Remove obsolete references to lock/.
diff --git a/Makefile.in b/Makefile.in
index ae92424bf8e..abd61490fbe 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -315,10 +315,21 @@ lib-src: FRC src/config.stamp
 # We need to build `emacs' in `src' to compile the *.elc files in `lisp'.
 lisp: src
 
+# Pass to src/Makefile.in an additional BOOTSTRAPEMACS variable which
+# is either set to bootstrap-emacs (in case bootstrap-emacs has not been
+# constructed yet) or the empty string (otherwise).
+# src/Makefile.in uses it to implement conditional dependencies, so that
+# files that need bootstrap-emacs to be built do not additionally need
+# to be kept fresher than bootstrap-emacs.  Otherwise changing a single
+# file src/foo.c forces dumping a new bootstrap-emacs, then re-byte-compiling
+# all preloaded elisp files, and only then dump the actual src/emacs, which
+# is not wrong, but is overkill in 99.99% of the cases.
 ${SUBDIR}: ${SUBDIR_MAKEFILES} FRC
-        cd $@; $(MAKE) all $(MFLAGS) \
+        boot=bootstrap-emacs$(EXEEXT);                         \
+        if [ -x "src/$$boot" ]; then boot=""; fi;                   \
+        cd $@; $(MAKE) all $(MFLAGS)                           \
           CC='${CC}' CFLAGS='${CFLAGS}' CPPFLAGS='${CPPFLAGS}' \
-          LDFLAGS='${LDFLAGS}' MAKE='${MAKE}'
+          LDFLAGS='${LDFLAGS}' MAKE='${MAKE}' BOOTSTRAPEMACS="$$boot"
 
 blessmail: ${SUBDIR_MAKEFILES} src FRC
         cd lib-src; $(MAKE) maybe-blessmail $(MFLAGS) \
diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index cd261b239d6..9fa1098b70b 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2008-06-22  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * Makefile.in (COMPILE_FIRST): Trim down and add autoload.el.
+
 2008-06-21  John Paul Wallington  <jpw@pobox.com>
 
         * emacs-lisp/derived.el (define-derived-mode): Add `doc-string' decl.
@@ -21,8 +25,8 @@
 
         * emacs-lisp/debug.el (help-xref-interned): Declare.
 
-        * emacs-lisp/easy-mmode.el (easy-mmode-set-keymap-parents): Evaluate
-        definition when compiling.
+        * emacs-lisp/easy-mmode.el (easy-mmode-set-keymap-parents):
+        Evaluate definition when compiling.
 
         * progmodes/bug-reference.el (bug-reference-map): Bind down-mouse-1
         rather than mouse-1.
diff --git a/lisp/Makefile.in b/lisp/Makefile.in
index d391080f493..7a94886735c 100644
--- a/lisp/Makefile.in
+++ b/lisp/Makefile.in
@@ -63,18 +63,11 @@ AUTOGENEL = loaddefs.el \
 
 # Files to compile before others during a bootstrap.  This is done to
 # speed up the bootstrap process.
-# Why `subr.elc'?  It's dumped so byte-compiling it early shouldn't make
-# any difference!?  --Stef
-# Some CC files are compiled first because CC mode tweaks the compilation
-# process, and requiring cc-mode when it is not compiled doesn't work during
-# the bootstrapping.
 
 COMPILE_FIRST = \
         $(lisp)/emacs-lisp/bytecomp.elc \
         $(lisp)/emacs-lisp/byte-opt.elc \
-        $(lisp)/subr.elc \
-        $(lisp)/progmodes/cc-mode.elc \
-        $(lisp)/progmodes/cc-vars.elc
+        $(lisp)/emacs-lisp/autoload.elc
 
 # The actual Emacs command run in the targets below.
 
@@ -145,7 +138,7 @@ autoloads: $(LOADDEFS) doit
         echo Directories: $$wins; \
         $(emacs) -l autoload --eval '(setq generated-autoload-file "$(lisp)/loaddefs.el")' -f batch-update-autoloads $$wins
 
-# This is required by the witness-emacs target in ../src/Makefile, so
+# This is required by the bootstrap-emacs target in ../src/Makefile, so
 # we know that if we have an emacs executable, we also have a subdirs.el.
 $(lisp)/subdirs.el:
         $(MAKE) $(MFLAGS) update-subdirs
diff --git a/src/ChangeLog b/src/ChangeLog
index 52b7bf078f4..fc0a84128b3 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,12 @@
+2008-06-22  Stefan Monnier  <monnier@iro.umontreal.ca>
+
+        * Makefile.in (${lisp} ${SOME_MACHINE_LISP}, ../lisp/loaddefs.el):
+        Use $(BOOTSTRAPEMACS) rather than witness-emacs.
+        (bootstrap-emacs${EXEEXT}): Merge witness-emacs into it.
+        (witness-emacs): Remove.
+        (lisp, shortlisp): Move loaddefs.el earlier.
+        (mostlyclean): Forget about witness-emacs.
+
 2008-06-22  Glenn Morris  <rgm@gnu.org>
 
         * Makefile.in (witness-emacs): Depend on temacs${EXEEXT}.
diff --git a/src/Makefile.in b/src/Makefile.in
index 8c85c2c4414..140f944e0d6 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -680,7 +680,11 @@ otherobj= $(termcapobj) lastfile.o $(mallocobj) $(widgetobj) $(LIBOBJS)
    Files included conditionally here should be included (unconditionally)
    in SOME_MACHINE_LISP.  */
 
+/* Please loaddefs.el first, so it gets generated first, since it is on
+   the critical path (relevant in parallel compilations).  */
+
 lisp= \
+        ${lispsource}loaddefs.el \
         ${lispsource}abbrev.elc \
         ${lispsource}buff-menu.elc \
         ${lispsource}button.elc \
@@ -705,7 +709,6 @@ lisp= \
         ${lispsource}isearch.elc \
         ${lispsource}rfn-eshadow.elc \
         ${lispsource}loadup.el \
-        ${lispsource}loaddefs.el \
         ${lispsource}bindings.elc \
         ${lispsource}emacs-lisp/map-ynp.elc \
         ${lispsource}menu-bar.elc \
@@ -775,6 +778,7 @@ lisp= \
    It need not contain the files that are loaded conditionally
    because SOME_MACHINE_LISP has those.  */
 shortlisp= \
+        ../lisp/loaddefs.el \
         ../lisp/abbrev.elc \
         ../lisp/buff-menu.elc \
         ../lisp/button.elc \
@@ -797,7 +801,6 @@ shortlisp= \
         ../lisp/isearch.elc \
         ../lisp/rfn-eshadow.elc \
         ../lisp/loadup.el \
-        ../lisp/loaddefs.el \
         ../lisp/bindings.elc \
         ../lisp/emacs-lisp/map-ynp.elc \
         ../lisp/env.elc \
@@ -1274,7 +1277,7 @@ ${emacsapp}Contents/MacOS/Emacs: emacs${EXEEXT}
 mostlyclean:
         rm -f temacs${EXEEXT} prefix-args${EXEEXT} core *.core \#* *.o libXMenu11.a liblw.a
         rm -f ../etc/DOC
-        rm -f bootstrap-emacs${EXEEXT} emacs-${version}${EXEEXT} witness-emacs
+        rm -f bootstrap-emacs${EXEEXT} emacs-${version}${EXEEXT}
         rm -f buildobj.lst
 clean: mostlyclean
         rm -f emacs-*.*.*${EXEEXT} emacs${EXEEXT}
@@ -1328,42 +1331,45 @@ tags: TAGS TAGS-LISP $(lwlibdir)TAGS
    To solve the circularity, we use 2 different Emacs executables,
    "emacs" is the main target and "bootstrap-emacs" is the one used
    to build the *.elc and loaddefs.el files.
-   To solve the freshness issue, we use a third file "witness-emacs"
-   which is used to witness the fact that there is a bootstrap-emacs
-   executable.  */
+   To solve the freshness issue, we used to use a third file "witness-emacs"
+   which was used to witness the fact that there is a bootstrap-emacs
+   executable, and then have dependencies on witness-emacs rather than
+   bootstrap-emacs, but that lead to problems in parallel builds (because
+   witness-emacs needed to be free from dependencies (to avoid rebuilding
+   it), so it was compiled in parallel, leading typically to having 2
+   processes dumping bootstrap-emacs at the same time).
+   So instead, we replace the witness-emacs dependencies by conditional
+   bootstrap-dependencies (via ${BOOTSTRAPEMACS}).  Of course, since we do
+   not want to rely on GNU Make features, we have to rely on an external
+   script to do the conditional part of the dependency
+   (i.e. see the ${SUBDIR} rule ../Makefile.in).  */
 
-/* These suffix rules do not allow additional dependencies, sadly, so
-   adding a bootstrap-emacs%{EXEEXT} dependency does not work --Stef */
 .SUFFIXES: .elc .el
 
+/* These suffix rules do not allow additional dependencies, sadly, so
+   instead of adding a $(BOOTSTRAPEMACS) dependency here, we add it
+   separately below.
+   With GNU Make, we would just say "%.el : %.elc $(BOOTSTRAPEMACS)"  */
 .el.elc:
         @cd ../lisp; $(MAKE) $(MFLAGS) compile-onefile \
-                            THEFILE=$< EMACS=../src/bootstrap-emacs${EXEEXT}
+                             THEFILE=$< EMACS=../src/bootstrap-emacs${EXEEXT}
 
-/* Since the .el.elc rule cannot specify an extra dependency, we do it here.
-   The byte-compiler dependency is not necessary, but it substantially
-   speeds up byte-compilation of the other files.
-   Of course, it also has the downside of forcing a recompilation of all
-   those files whenever a file in $PRECOMP changes.  */
-${lisp} ${SOME_MACHINE_LISP}: witness-emacs
+/* Since the .el.elc rule cannot specify an extra dependency, we do it here.  */
+${lisp} ${SOME_MACHINE_LISP}: $(BOOTSTRAPEMACS)
 
-../lisp/loaddefs.el: witness-emacs
+../lisp/loaddefs.el: $(BOOTSTRAPEMACS)
         cd ../lisp; $(MAKE) $(MFLAGS) autoloads EMACS=../src/bootstrap-emacs${EXEEXT}
 
 /* Dump an Emacs executable named bootstrap-emacs containing the
    files from loadup.el in source form.  */
 
 bootstrap-emacs${EXEEXT}: temacs${EXEEXT}
+        cd ../lisp; $(MAKE) $(MFLAGS) update-subdirs
 #ifdef CANNOT_DUMP
         ln temacs${EXEEXT} bootstrap-emacs${EXEEXT}
 #else
         $(RUN_TEMACS) --batch --load loadup bootstrap
         mv -f emacs${EXEEXT} bootstrap-emacs${EXEEXT}
 #endif /* ! defined (CANNOT_DUMP) */
-
-witness-emacs: temacs${EXEEXT}
-        cd ../lisp; $(MAKE) $(MFLAGS) update-subdirs
-        $(MAKE) $(MFLAGS) bootstrap-emacs${EXEEXT}
-        touch witness-emacs
         @: Compile some files earlier to speed up further compilation.
         cd ../lisp; $(MAKE) $(MFLAGS) compile-first EMACS=../src/bootstrap-emacs${EXEEXT}