coverage: compile rules used "-c -o" also with losing compilers

If the 'subdir-objects' option is used, Automake-generated rules for
C compilation pass both the "-c" and "-o" options to the C compiler,
*unconditionally*.  There are some compilers that choke on such an
usage, but the AM_PROG_CC_C_O macro takes care of them (it does so by
redefining $CC to use the Automake-provided 'compile' wrapper script
automatically, if a losing compiler is detected at configure runtime).

Unfortunately, in case the 'subdir-objects' option is specified in a
Makefile.am, but all the source files resided anyway in the top-level
directory (relative to the Makefile.am), Automake do *not* complain
if AM_PROG_CC_C_O wasn't invoked in 'configure.ac' -- all the while
still passing "-c -o" to the compiler invocations.  This could cause
compilation failures with losing compilers if the user forget to call
AM_PROG_CC_C_O in 'configure.ac' (and Automake would not warn him of
the issue).

Expose this bug in the testsuite.

Issue identified by Nick Bowler in the discussion on automake bug#13378:
<http://debbugs.gnu.org/cgi/bugreport.cgi?bug=13378#35>
<http://debbugs.gnu.org/cgi/bugreport.cgi?bug=13378#44>

* t/ccnoco4.sh: New test.
* t/list-of-tests.mk (XFAIL_TESTS, handwritten_TESTS): List it.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>

diff --git a/t/ccnoco4.sh b/t/ccnoco4.sh
new file mode 100755 (executable)
index 0000000..54b857a
--- /dev/null
+++ b/t/ccnoco4.sh
@@ -0,0 +1,70 @@
+#! /bin/sh
+# Copyright (C) 2001-2013 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/>.
+
+# Check that Automake doesn't pass "-c -o" to  losing compiler when
+# the 'subdir-objects' is used but sources are only present in the
+# top-level directory.  Reported by Nick Bowler in the discussion on
+# automake bug#13378:
+# <http://debbugs.gnu.org/cgi/bugreport.cgi?bug=13378#35>
+# <http://debbugs.gnu.org/cgi/bugreport.cgi?bug=13378#44>
+
+required=gcc
+. test-init.sh
+
+# We deliberately do not call AM_PROG_CC_C_O here.
+cat >> configure.ac << 'END'
+AC_PROG_CC
+$CC --version; $CC -v; # For debugging.
+AC_OUTPUT
+END
+
+cat > Makefile.am << 'END'
+AUTOMAKE_OPTIONS = subdir-objects
+bin_PROGRAMS = foo bar
+bar_SOURCES = foo.c
+END
+
+echo 'int main (void) { return 0; }' > foo.c
+
+cat > Mycomp << END
+#!/bin/sh
+
+case " \$* " in
+ *\ -c*\ -o* | *\ -o*\ -c*)
+    exit 1
+    ;;
+esac
+
+# Use '$CC', not 'gcc', to honour the compiler chosen
+# by the testsuite setup.
+exec $CC "\$@"
+END
+
+chmod +x Mycomp
+
+# Make sure the compiler doesn't understand '-c -o'.
+CC=$(pwd)/Mycomp
+export CC
+
+$ACLOCAL
+$AUTOCONF
+$AUTOMAKE --copy --add-missing
+
+./configure
+$MAKE
+$MAKE distcheck
+
+:

diff --git a/t/list-of-tests.mk b/t/list-of-tests.mk
index f3e9963255cbc821d2b17e56196d856d4fb64978..aef3730e22317668864525ca14f15d198b325346 100644 (file)
--- a/t/list-of-tests.mk
+++ b/t/list-of-tests.mk
@@ -30,6 +30,7 @@ t/pm/Version3.pl
 
 XFAIL_TESTS = \
 t/all.sh \
+t/ccnoco4.sh \
 t/cond17.sh \
 t/gcj6.sh \
 t/override-conditional-2.sh \
@@ -209,6 +210,7 @@ t/canon-name.sh \
 t/ccnoco.sh \
 t/ccnoco2.sh \
 t/ccnoco3.sh \
+t/ccnoco4.sh \
 t/check.sh \
 t/check2.sh \
 t/check4.sh \