GNUmakefile: disable parallelism only for multiple, recursive targets

* top/GNUmakefile (ALL_RECURSIVE_TARGETS): New macro; allow user
additions in the Makefile.
(AM_RECURSIVE_TARGETS): New macro, override only if not provided
by Automake.
(.NOTPARALLEL): Only disable parallel builds if multiple targets
are listed on the command line and at least one of them is
listed in $(ALL_RECURSIVE_TARGETS).

Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>

diff --git a/ChangeLog b/ChangeLog
index bd7d4501c592fd74c355d506ae6989b50a05cb7d..f33be940505b41f1f368b2da98280b507bf387f3 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2009-03-14  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
+
+       GNUmakefile: disable parallelism only for multiple, recursive targets
+       * top/GNUmakefile (ALL_RECURSIVE_TARGETS): New macro; allow user
+       additions in the Makefile.
+       (AM_RECURSIVE_TARGETS): New macro, override only if not provided
+       by Automake.
+       (.NOTPARALLEL): Only disable parallel builds if multiple targets
+       are listed on the command line and at least one of them is
+       listed in $(ALL_RECURSIVE_TARGETS).
+
 2009-03-14  Bruno Haible  <bruno@clisp.org>
 
        * modules/unilbrk/u8-possible-linebreaks (Depends-on): Replace

diff --git a/top/GNUmakefile b/top/GNUmakefile
index 0fdd3fa7357d6ba8ea7b7299b2546a2165c9a8e2..14b6fcdcebf4a4e6d4f03e9cac7ec9d1be088b0b 100644 (file)
--- a/top/GNUmakefile
+++ b/top/GNUmakefile
@@ -5,7 +5,7 @@
 # It is necessary if you want to build targets usually of interest
 # only to the maintainer.
 
-# Copyright (C) 2001, 2003, 2006-2008 Free Software Foundation, Inc.
+# Copyright (C) 2001, 2003, 2006-2009 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -38,6 +38,9 @@ ifeq ($(_have-Makefile),yes)
 # Make tar archive easier to reproduce.
 export TAR_OPTIONS = --owner=0 --group=0 --numeric-owner
 
+# Allow the user to add to this in the Makefile.
+ALL_RECURSIVE_TARGETS =
+
 include Makefile
 
 # Some projects override e.g., _autoreconf here.
@@ -107,6 +110,18 @@ abort-due-to-no-makefile:
 endif
 
 # Tell version 3.79 and up of GNU make to not build goals in this
-# directory in parallel.  This is necessary in case someone tries to
-# build multiple targets on one command line.
+# directory in parallel, in case someone tries to build multiple
+# targets, and one of them can cause a recursive target to be invoked.
+
+# Only set this if Automake doesn't provide it.
+AM_RECURSIVE_TARGETS ?= $(RECURSIVE_TARGETS:-recursive=) \
+  $(RECURSIVE_CLEAN_TARGETS:-recursive=) \
+  dist distcheck tags ctags
+
+ALL_RECURSIVE_TARGETS += $(AM_RECURSIVE_TARGETS)
+
+ifneq ($(word 2, $(MAKECMDGOALS)), )
+ifneq ($(filter $(ALL_RECURSIVE_TARGETS), $(MAKECMDGOALS)), )
 .NOTPARALLEL:
+endif
+endif