Speed generation of ldefs-boot-auto

Previously, generation of ldefs-boot-auto required at least one full
bootstrap and, in extreme cases, two. Now, from build system, it
requires the same time as taken to dump Emacs.

* Makefile.in: Remove all calls, pass to src.
* admin/ldefs-clean.el: Update for changed messages.
* lisp/Makefile.in (compile-first-delete): Add.
* lisp/ldefs-boot-auto.el: Update.
* src/Makefile.in (generate-ldefs-boot): Add.

1 files changed, 23 insertions, 2 deletions

diff --git a/src/Makefile.in b/src/Makefile.in
index ab319837249..730f79801c3 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -761,9 +761,30 @@ endif
         @: Compile some files earlier to speed up further compilation.
         $(MAKE) -C ../lisp compile-first EMACS="$(bootstrap_exe)"
 
+shortlisp-keep=loadup.el loaddefs.el
+
+## Generating ldefs-boot-auto.el requires that we dump both emacs and
+## the bootstrap-emacs so that we can see which autoloads are actually
+## called.  This is a slightly messy affair as we must ensure that
+## they are build as if from clean, which means deleting all the build
+## files first.  We use loaddefs.el to make sure that we can build
+## from bootstrap; obviously, this assumes that loaddefs.el already
+## exists or we have a bootstrap problem!
+generate-ldefs-boot: $(lispsource)/loaddefs.el
+        echo Cleaning to enable generate-ldefs-boot
+        mv $(lispsource)/loaddefs.el $(lispsource)/ldefs-boot-auto.el
+        $(MAKE) -C $(lispsource) compile-first-delete
+        -for f in $(filter-out $(shortlisp-keep), $(shortlisp)); do test -e $(lispsource)/$$f && rm -v $(lispsource)/$$f; done
+        - rm bootstrap-emacs$(EXEEXT)
+        - rm emacs$(EXEEXT)
+        echo Building generate-ldefs-boot
+        $(MAKE) -j 1 emacs$(EXEEXT) \
+        GENERATE_LDEFS_BOOT="generate-ldefs-boot" \
+        2>&1 | tee $(lispsource)/ldefs-boot-auto.temp
+        echo Reformatting ldefs-boot-auto.el
+        emacs$(EXEEXT) -batch --load ../admin/ldefs-clean.el --funcall ldefs-clean
+        rm ../lisp/ldefs-boot-auto.temp
 
-generate-ldefs-boot: bootstrap-emacs$(EXEEXT)
-        $(RUN_TEMACS) --batch $(BUILD_DETAILS) --load loadup bootstrap
 
 ifeq ($(AUTO_DEPEND),yes)
 -include $(ALLOBJS:%.o=${DEPDIR}/%.d)