bug#13940: Spurious target redefinition warnings with Automake conditionals

[Stefano Lattarini]

[+cc automake-patches]

On 03/13/2013 02:40 AM, Nick Bowler wrote:
> Consider the following:
> 
>   % cat >configure.ac <<'EOF'
> AC_INIT([test], [0])
> 
> AM_INIT_AUTOMAKE([foreign])
> 
> AM_CONDITIONAL([FOO], [true])
> 
> AC_CONFIG_FILES([Makefile])
> AC_OUTPUT
> EOF
> 
>   % cat >Makefile.am <<'EOF'
> if FOO
> all-local: bar
> bar: ; @echo bar
> endif
> 
> all-local: baz
> baz: ; @echo baz
> EOF
> 
> On this input, Automake is producing the following warning:
> 
>   Makefile.am:6: warning: all-local was already defined in condition
> FOO, which is included in condition TRUE ...
>   Makefile.am:2: ... 'all-local' previously defined here
> 
> This warning makes no sense, because there is no problem with this
> Makefile.am as far as I can see.  However, the warnings seem to be just
> noise as the generated Makefile.in appears correct and works fine.
> 
> The conditional there is important: Automake only appears to warn when
> one of the all-local rules is inside a conditional and the other is not.
> 
>
I've exposed the bug with the patch inlined below.  Not sure when I'll
be able to attempt a proper fix.  If anyone wants to give it a try in
the meantime, be my guest!

Thanks,
  Stefano

---- 8< ---- 8< ---- 8< ---- 8< ---- 8< ---- 8< ---- 8< ---- 8< ----

>From b2b3692d37e9812a5895b5a054da597731d7eb08 Mon Sep 17 00:00:00 2001
Message-Id: <address@hidden>
From: Stefano Lattarini <address@hidden>
Date: Sat, 8 Jun 2013 17:47:30 +0200
Subject: [PATCH] tests: expose automake bug#13940

* t/override-conditional-pr13940.sh: New test, still xfailing.
* t/list-of-tests.mk (XFAIL_TESTS, handwritten_TESTS): Add it.

Signed-off-by: Stefano Lattarini <address@hidden>
---
 t/list-of-tests.mk                |  2 ++
 t/override-conditional-pr13940.sh | 44 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 t/override-conditional-pr13940.sh

diff --git a/t/list-of-tests.mk b/t/list-of-tests.mk
index fb2e444..68ca58c 100644
--- a/t/list-of-tests.mk
+++ b/t/list-of-tests.mk
@@ -33,6 +33,7 @@ t/all.sh \
 t/cond17.sh \
 t/gcj6.sh \
 t/override-conditional-2.sh \
+t/override-conditional-pr13940.sh \
 t/dist-pr109765.sh \
 t/instdir-cond2.sh \
 t/java-nobase.sh \
@@ -740,6 +741,7 @@ t/output13.sh \
 t/output-order.sh \
 t/override-conditional-1.sh \
 t/override-conditional-2.sh \
+t/override-conditional-pr13940.sh \
 t/override-html.sh \
 t/override-suggest-local.sh \
 t/parallel-am.sh \
diff --git a/t/override-conditional-pr13940.sh 
b/t/override-conditional-pr13940.sh
new file mode 100644
index 0000000..4bc4128
--- /dev/null
+++ b/t/override-conditional-pr13940.sh
@@ -0,0 +1,44 @@
+#! /bin/sh
+# Copyright (C) 2013 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/>.
+
+# Expose automake bug#1394: automake erroneously think that a .PHONY
+# target's rule is overridden only because we declare dependencies
+# to such targets twice: one in an Automake conditional, and once
+# unconditionally.
+
+. test-init.sh
+
+cat >> configure.ac << 'END'
+AM_CONDITIONAL([FOO], [true])
+AC_OUTPUT
+END
+
+cat > Makefile.am << 'END'
+# The conditional here is important: Automake only appears to warn
+# when one of the all-local rules is inside a conditional and the
+# other is not.
+if FOO
+all-local: bar
+bar: ; @echo bar
+endif
+all-local: baz
+baz: ; @echo baz
+END
+
+$ACLOCAL
+$AUTOMAKE -a
+
+:
-- 
1.8.3.rc3.8.g5e49f30