Empty elements in EMACSLOADPATH now stand for the default

* src/lread.c (load_path_check): Take path to check as argument.
(load_path_default): New, split from init_lread.
(init_lread): Move calc of default load-path to load_path_default.
Empty elements in EMACSLOADPATH now stand for the default.
(load-path): Doc fix.

* src/emacs.c (decode_env_path): Add option to treat empty elements
as nil rather than ".".

* src/callproc.c (init_callproc_1, init_callproc):
* src/image.c (Vx_bitmap_file_path):
* src/lisp.h (decode_env_path):
* lread.c (Vsource_directory):
Update for new argument spec of decode_env_path.

* leim/Makefile.in (RUN_EMACS): Empty EMACSLOADPATH rather than unsetting.

* lisp/Makefile.in (emacs): Empty EMACSLOADPATH rather than unsetting.

* test/automated/Makefile.in (emacs):
Empty EMACSLOADPATH rather than unsetting.

* doc/emacs/cmdargs.texi (General Variables):
Empty elements in EMACSLOADPATH now mean the default load-path.

* doc/lispref/loading.texi (Library Search):
Empty elements in EMACSLOADPATH now mean the default load-path.

* etc/NEWS: Mention this.

Fixes: debbugs:12100

2 files changed, 5 insertions, 1 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index f9b6f6ee356..97f4c007c72 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2013-11-23  Glenn Morris  <rgm@gnu.org>
+
+        * Makefile.in (emacs): Empty EMACSLOADPATH rather than unsetting.
+
 2013-11-22  Leo Liu  <sdl.web@gmail.com>
 
         * progmodes/octave.el (inferior-octave-startup): Spit out error
diff --git a/lisp/Makefile.in b/lisp/Makefile.in
index d00330c3a9b..eb52b317e7b 100644
--- a/lisp/Makefile.in
+++ b/lisp/Makefile.in
@@ -106,7 +106,7 @@ COMPILE_FIRST = \
 
 # The actual Emacs command run in the targets below.
 # Prevent any setting of EMACSLOADPATH in user environment causing problems.
-emacs = unset EMACSLOADPATH; "$(EMACS)" $(EMACSOPT)
+emacs = EMACSLOADPATH= "$(EMACS)" $(EMACSOPT)
 
 # Common command to find subdirectories
 setwins=for file in `find . -type d -print`; do \