[PATCH] Don't let an envvar setting of "$fail" cause build failure.

[Jim Meyering]

Hi Ralf,

While fixing similar problems in coreutils' test suite, I found
that with an automake-generated Makefile, "make" always fails
when I set e.g, fail=1 in the environment.

This fix works for me in that now, with regenerated Makefile.in files,
coreutils' "make check fail=1" now passes.

>From ffcd00af02f97d8990ee0f45ab82706803f10578 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Fri, 30 Oct 2009 12:02:22 +0100
Subject: [PATCH] Don't let an envvar setting of "$fail" cause build failure.

Without this change, in a project using an automake-generated
Makefile, "make fail=anything" would fail inappropriately,
due to the `test -z "$$fail"' at the end of this emitted rule:
* lib/am/subdirs.am ($(RECURSIVE_TARGETS)): Initialize "fail=" to keep
an envvar setting of that variable from causing unwarranted failure.
($(RECURSIVE_CLEAN_TARGETS)): Likewise.
---
 ChangeLog         |   10 ++++++++++
 lib/am/subdirs.am |    4 ++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 2fe0566..90af382 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2009-10-30  Jim Meyering  <address@hidden>
+
+       Don't let an envvar setting of "$fail" cause build failure.
+       Without this change, in a project using an automake-generated
+       Makefile, "make fail=anything" would fail inappropriately,
+       due to the `test -z "$$fail"' at the end of this emitted rule:
+       * lib/am/subdirs.am ($(RECURSIVE_TARGETS)): Initialize "fail=" to keep
+       an envvar setting of that variable from causing unwarranted failure.
+       ($(RECURSIVE_CLEAN_TARGETS)): Likewise.
+
 2009-10-18  Ralf Wildenhues  <address@hidden>

        Simplify Variable::_check_ambiguous_condition.
diff --git a/lib/am/subdirs.am b/lib/am/subdirs.am
index b86e674..9c01a8c 100644
--- a/lib/am/subdirs.am
+++ b/lib/am/subdirs.am
@@ -36,7 +36,7 @@ AM_RECURSIVE_TARGETS += $(RECURSIVE_TARGETS:-recursive=) \
 $(RECURSIVE_TARGETS):
 ## Using $failcom allows "-k" to keep its natural meaning when running a
 ## recursive rule.
-       @failcom='exit 1'; \
+       @fail= failcom='exit 1'; \
        for f in x $$MAKEFLAGS; do \
          case $$f in \
            *=* | --[!k]*);; \
@@ -75,7 +75,7 @@ maintainer-clean: maintainer-clean-recursive
 $(RECURSIVE_CLEAN_TARGETS):
 ## Using $failcom allows "-k" to keep its natural meaning when running a
 ## recursive rule.
-       @failcom='exit 1'; \
+       @fail= failcom='exit 1'; \
        for f in x $$MAKEFLAGS; do \
          case $$f in \
            *=* | --[!k]*);; \
--
1.6.5.2.375.g164f1