Fix 'make man' for parallel make

Ensure the Python Lex/Yacc (PLY) cache used by makedocbook is initialized
before it is used by parallelizable rules to make the DocBook XML, as it
appears that these can collide in cache generation, leading to errors.

Signed-off-by: Jon Turney <jon.turney@dronecode.org.uk>

newlib/Makefile.am

@@ -364,6 +364,7 @@ doc/makedoc:
 
 # Recursive targets for man and install-man
 man:
+	(cd doc && $(MAKE) man-cache) || exit 1; \
 	for d in $(SUBDIRS); do \
 	  if test "$$d" != "."; then \
 	    (cd $$d && $(MAKE) man) || exit 1; \

newlib/Makefile.in

@@ -1116,6 +1116,7 @@ doc/makedoc:
 
 # Recursive targets for man and install-man
 man:
+	(cd doc && $(MAKE) man-cache) || exit 1; \
 	for d in $(SUBDIRS); do \
 	  if test "$$d" != "."; then \
 	    (cd $$d && $(MAKE) man) || exit 1; \

newlib/doc/Makefile.am

@@ -21,3 +21,8 @@ ACLOCAL_AMFLAGS = -I .. -I ../..
 CONFIG_STATUS_DEPENDENCIES = $(newlib_basedir)/configure.host
 
 man:
+
+man-cache:
+	${srcdir}/makedocbook.py --cache
+
+.PHONY: man-cache

newlib/doc/Makefile.in

@@ -358,6 +358,11 @@ makedoc.o: makedoc.c
 
 man:
 
+man-cache:
+	${srcdir}/makedocbook.py --cache
+
+.PHONY: man-cache
+
 # Tell versions [3.59,3.63) of GNU make to not export all variables.
 # Otherwise a system limit (for SysV at least) may be exceeded.
 .NOEXPORT:

newlib/doc/makedocbook.py

@@ -824,8 +824,12 @@ def main(file):
 if __name__ == '__main__' :
     options = OptionParser()
     options.add_option('-v', '--verbose', action='count', dest = 'verbose')
+    options.add_option('-c', '--cache', action='store_true', dest = 'cache', help="just ensure PLY cache is up to date")
     (opts, args) = options.parse_args()
 
+    if opts.cache:
+	sys.exit()
+
     verbose = opts.verbose
 
     if len(args) > 0: