On Friday 05 November 2010, Stefano Lattarini wrote:
I can confirm the bug with latest automake (from git master), with
a much-reduced minimal testcase (see attachment).
I still haven't looked for an explanation or a fix, though.
I've manged to find a very simple fix for the bug (see attached patch).
OK to apply to maint?
Regards,
Stefano
From b8de299295e081909c6d0a8a1cef957b337e3732 Mon Sep 17 00:00:00 2001
From: Stefano Lattarini stefano.lattar...@gmail.com
Date: Sat, 6 Nov 2010 12:46:52 +0100
Subject: [PATCH] Fix a bug in variable concatanation with `+='.
* lib/Automake/VarDef.pm (append): Remove extra backslash-escaped
newlines from the end of the variable's content, before appending
to it.
* tests/pluseq11.test: New test, exposing the bug.
* tests/Makefile.am (TESTS): Update.
Reported by Andy Wingo.
---
ChangeLog | 10
lib/Automake/VarDef.pm | 13 +-
tests/Makefile.am |1 +
tests/Makefile.in |1 +
tests/pluseq11.test| 54
5 files changed, 68 insertions(+), 11 deletions(-)
create mode 100755 tests/pluseq11.test
diff --git a/ChangeLog b/ChangeLog
index 6c17cd3..a928363 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2010-11-06 Stefano Lattarini stefano.lattar...@gmail.com
+
+ Fix a bug in variable concatanation with `+='.
+ * lib/Automake/VarDef.pm (append): Remove extra backslash-escaped
+ newlines from the end of the variable's content, before appending
+ to it.
+ * tests/pluseq11.test: New test, exposing the bug.
+ * tests/Makefile.am (TESTS): Update.
+ Reported by Andy Wingo.
+
2010-11-01 Ralf Wildenhues ralf.wildenh...@gmx.de
Fix and document rules to not touch the tree with `make -n'.
diff --git a/lib/Automake/VarDef.pm b/lib/Automake/VarDef.pm
index d7ba155..568c82a 100644
--- a/lib/Automake/VarDef.pm
+++ b/lib/Automake/VarDef.pm
@@ -185,17 +185,8 @@ sub append ($$$)
# Furthermore keeping `#' would not be portable if the variable is
# output on multiple lines.
$val =~ s/ ?#.*//;
-
- if (chomp $val)
-{
- # Insert a backslash before a trailing newline.
- $val .= \\\n;
-}
- elsif ($val)
-{
- # Insert a separator.
- $val .= ' ';
-}
+ # Insert a separator, if required.
+ $val .= ' ' if $val;
$self-{'value'} = $val . $value;
# Turn ASIS appended variables into PRETTY variables. This is to
# cope with `make' implementation that cannot read very long lines.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 9c81564..da81c49 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -570,6 +570,7 @@ pluseq7.test \
pluseq8.test \
pluseq9.test \
pluseq10.test \
+pluseq11.test \
postproc.test \
ppf77.test \
pr2.test \
diff --git a/tests/Makefile.in b/tests/Makefile.in
index b568a09..eb461a9 100644
--- a/tests/Makefile.in
+++ b/tests/Makefile.in
@@ -837,6 +837,7 @@ pluseq7.test \
pluseq8.test \
pluseq9.test \
pluseq10.test \
+pluseq11.test \
postproc.test \
ppf77.test \
pr2.test \
diff --git a/tests/pluseq11.test b/tests/pluseq11.test
new file mode 100755
index 000..293270f
--- /dev/null
+++ b/tests/pluseq11.test
@@ -0,0 +1,54 @@
+#!/bin/sh
+# Copyright (C) 2010 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
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see http://www.gnu.org/licenses/.
+
+# Check for bug in variable concatenation with `+=': an extra backslash
+# is erroneously retained in the final value.
+# See also sister test pluseq11b.test.
+
+. ./defs || Exit 1
+
+set -e
+
+cat configure.in 'END'
+AC_OUTPUT
+END
+
+cat Makefile.am 'END'
+## Use more line continuation to ensure we are robust and can (hopefully)
+## cope any number of them, and not just one
+FOO = \
+\
+\
+bar
+## Both this two variable additions are required to trigger the bug.
+FOO +=
+FOO += baz
+
+.PHONY: test
+test:
+ case '$(FOO)' in *\\*) exit 1;; *) exit 0;; esac
+END
+
+$ACLOCAL
+$AUTOMAKE
+
+grep '^ *FOO *=.*\\.' Makefile.in Exit 1
+
+$AUTOCONF
+./configure
+$MAKE test
+
+:
--
1.7.1
