Package: automake;
Reported by: Paul Eggert <eggert <at> cs.ucla.edu>
Date: Tue, 6 Dec 2011 17:53:02 UTC
Severity: minor
Tags: patch
Done: Stefano Lattarini <stefano.lattarini <at> gmail.com>
Bug is archived. No further changes may be made.
Message #75 received at 10237 <at> debbugs.gnu.org (full text, mbox):
From: Paul Eggert <eggert <at> cs.ucla.edu> To: Stefano Lattarini <stefano.lattarini <at> gmail.com> Cc: 9928 <at> debbugs.gnu.org, Eric Blake <eblake <at> redhat.com>, 10237 <at> debbugs.gnu.org, skunk <at> iskunk.org Subject: Re: bug#10237: AM_SILENT_RULES does not work with NonStop make Date: Tue, 20 Dec 2011 17:30:20 -0800
On 12/11/11 01:42, Stefano Lattarini wrote:
> I was asking for a test case that simulates the presence of a
> make implementation unable to grasp nested variable expansions
Ah, OK, revised patch enclosed below. This patch should address
your other comments too. Thanks for the careful review.
From 07edd4aa81af2a8fb982427705a2009c2b7eb0bf Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert <at> cs.ucla.edu>
Date: Tue, 20 Dec 2011 17:29:06 -0800
Subject: [PATCH] automake: silent-rules no longer requires nested vars
This fixes two problems reported for Automake (Bug#9928, Bug#10237)
and is in response to a bug report for building coreutils on HP
NonStop OS (Bug#10234). The problem is that HP NonStop 'make'
treats a line like "AM_V_CC = $(am__v_CC_$(V))" as one that
expands a macro with the funny name am__v_CC_$(V instead of the
desired name am__v_CC_1 or am__v_CC_0, and since the funny macro
is not defined the line is equivalent to "AM_V_CC = )"; this
inserts a stray ")" when $(AM_V_CC) is used, which eventually
causes 'make' to fail.
The basic idea is that instead of generating Makefile.in lines like
"AM_V_CC = $(am__v_CC_$(V))", we generate
"AM_V_CC = $(am__v_CC_ <at> AM_V@)". We then AC_SUBST $(V) for @AM_V@
in the usual case where `make' supports nested variables,
and substitute 1 (or 0) otherwise. Similarly for usages like
$(am__v_CC_$(AM_DEFAULT_VERBOSITY)).
With this change, make implementations that doesn't grasp nested
variable expansions will still be able to run Makefiles generated
using the silent-rules option. They won't allow the user to
override the make verbosity at runtime through redefinition of
$(V) (as in "make V=0"); but this is still an improvement over not
being able to work at all.
* NEWS: Document this.
* automake.in (define_verbose_var): When defining the variable,
use @AM_V@ rather than $(V), and use
@AM_AM_DEFAULT_VERBOSITY@ rather than $(AM_DEFAULT_VERBOSITY).
* doc/automake.texi (Automake silent-rules Option): Explain new system.
* m4/silent.m4 (AM_SILENT_RULES): Check whether `make' supports
nested variables, and substitute AM_V and AM_AM_DEFAULT_VERBOSITY
accordingly.
* tests/silent-nested-vars.test: New file.
* tests/Makefile.am (TESTS): Add it.
* tests/Makefile.in: Regenerate.
---
ChangeLog | 40 +++++++++++++++
NEWS | 7 +++
automake.in | 9 ++-
doc/automake.texi | 22 +++++----
m4/silent.m4 | 33 +++++++++++-
tests/Makefile.am | 1 +
tests/Makefile.in | 1 +
tests/silent-nested-vars.test | 111 +++++++++++++++++++++++++++++++++++++++++
8 files changed, 209 insertions(+), 15 deletions(-)
create mode 100755 tests/silent-nested-vars.test
diff --git a/ChangeLog b/ChangeLog
index 49b6e8b..b2d6e11 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,43 @@
+2011-12-11 Paul Eggert <eggert <at> cs.ucla.edu>
+
+ automake: silent-rules no longer requires nested vars
+
+ This fixes two problems reported for Automake (Bug#9928, Bug#10237)
+ and is in response to a bug report for building coreutils on HP
+ NonStop OS (Bug#10234). The problem is that HP NonStop 'make'
+ treats a line like "AM_V_CC = $(am__v_CC_$(V))" as one that
+ expands a macro with the funny name am__v_CC_$(V instead of the
+ desired name am__v_CC_1 or am__v_CC_0, and since the funny macro
+ is not defined the line is equivalent to "AM_V_CC = )"; this
+ inserts a stray ")" when $(AM_V_CC) is used, which eventually
+ causes 'make' to fail.
+
+ The basic idea is that instead of generating Makefile.in lines like
+ "AM_V_CC = $(am__v_CC_$(V))", we generate
+ "AM_V_CC = $(am__v_CC_ <at> AM_V@)". We then AC_SUBST $(V) for @AM_V@
+ in the usual case where `make' supports nested variables,
+ and substitute 1 (or 0) otherwise. Similarly for usages like
+ $(am__v_CC_$(AM_DEFAULT_VERBOSITY)).
+
+ With this change, make implementations that doesn't grasp nested
+ variable expansions will still be able to run Makefiles generated
+ using the silent-rules option. They won't allow the user to
+ override the make verbosity at runtime through redefinition of
+ $(V) (as in "make V=0"); but this is still an improvement over not
+ being able to work at all.
+
+ * NEWS: Document this.
+ * automake.in (define_verbose_var): When defining the variable,
+ use @AM_V@ rather than $(V), and use
+ @AM_AM_DEFAULT_VERBOSITY@ rather than $(AM_DEFAULT_VERBOSITY).
+ * doc/automake.texi (Automake silent-rules Option): Explain new system.
+ * m4/silent.m4 (AM_SILENT_RULES): Check whether `make' supports
+ nested variables, and substitute AM_V and AM_AM_DEFAULT_VERBOSITY
+ accordingly.
+ * tests/silent-nested-vars.test: New file.
+ * tests/Makefile.am (TESTS): Add it.
+ * tests/Makefile.in: Regenerate.
+
2011-12-20 Peter Rosin <peda <at> lysator.liu.se>
tests: fix spurious failure on systems lacking unistd.h
diff --git a/NEWS b/NEWS
index 46803a7..58c90c9 100644
--- a/NEWS
+++ b/NEWS
@@ -74,6 +74,13 @@ Bugs fixed in 1.11.0a:
not used, `make' output no longer contains spurious backslash-only
lines, thus once again matching what Automake did before 1.11.
+ - The `silent-rules' option now generates working makefiles even for
+ the uncommon `make' implementations that do not support the
+ nested-variables extension to POSIX 2008. For such `make'
+ implementations, whether a build is silent is determined at
+ configure time, and cannot be overridden at make time with `make
+ V=0' or `make V=1'.
+
- The AM_COND_IF macro also works if the shell expression for the conditional
is no longer valid for the condition.
diff --git a/automake.in b/automake.in
index db7f3c6..ae2011c 100755
--- a/automake.in
+++ b/automake.in
@@ -1161,9 +1161,12 @@ sub define_verbose_var ($$)
my $silent_var = $pvar . '_0';
if (option 'silent-rules')
{
- # Using `$V' instead of `$(V)' breaks IRIX make.
- define_variable ($var, '$(' . $pvar . '_$(V))', INTERNAL);
- define_variable ($pvar . '_', '$(' . $pvar . '_$(AM_DEFAULT_VERBOSITY))', INTERNAL);
+ # For typical `make's, `configure' replaces AM_V (inside @@) with $(V)
+ # and AM_AM_DEFAULT_VERBOSITY (inside @@) with $(AM_DEFAULT_VERBOSITY).
+ # For strict POSIX 2008 `make's, it replaces them with 0 or 1 instead.
+ # See AM_SILENT_RULES in m4/silent.m4.
+ define_variable ($var, '$(' . $pvar . '_@'.'AM_V'.'@)', INTERNAL);
+ define_variable ($pvar . '_', '$(' . $pvar . '_@'.'AM_AM_DEFAULT_VERBOSITY'.'@)', INTERNAL);
Automake::Variable::define ($silent_var, VAR_AUTOMAKE, '', TRUE, $val,
'', INTERNAL, VAR_ASIS)
if (! vardef ($silent_var, TRUE));
diff --git a/doc/automake.texi b/doc/automake.texi
index a5f857d..1a689b6 100644
--- a/doc/automake.texi
+++ b/doc/automake.texi
@@ -10130,18 +10130,20 @@ For portability to different @command{make} implementations, package authors
are advised to not set the variable @code{V} inside the @file{Makefile.am}
file, to allow the user to override the value for subdirectories as well.
-The current implementation of this feature relies on a non-POSIX, but in
-practice rather widely supported @file{Makefile} construct of nested
-variable expansion @samp{$(@var{var1}$(V))}. Do not use the
-@option{silent-rules} option if your package needs to build with
-@command{make} implementations that do not support it. The
-@option{silent-rules} option turns off warnings about recursive variable
-expansion, which are in turn enabled by @option{-Wportability}
-(@pxref{Invoking Automake}).
+The current implementation of this feature normally uses nested
+variable expansion @samp{$(@var{var1}$(V))}, a @file{Makefile} feature
+that is not required by POSIX 2008 but is widely supported in
+practice. On the rare @command{make} implementations that do not
+support nested variable expansion, whether rules are silent is always
+determined at configure time, and cannot be overridden at make time.
+Future versions of POSIX are likely to require nested variable
+expansion, so this minor limitation should go away with time.
@vindex @code{AM_V_GEN}
@vindex @code{AM_V_at}
@vindex @code{AM_DEFAULT_VERBOSITY}
+@vindex @code{AM_V}
+@vindex @code{AM_AM_DEFAULT_VERBOSITY}
To extend the silent mode to your own rules, you have two choices:
@itemize @bullet
@@ -10157,8 +10159,8 @@ The following snippet shows how you would define your own equivalent of
@code{AM_V_GEN}:
@example
-pkg_verbose = $(pkg_verbose_$(V))
-pkg_verbose_ = $(pkg_verbose_$(AM_DEFAULT_VERBOSITY))
+pkg_verbose = $(pkg_verbose_@@AM_V@@)
+pkg_verbose_ = $(pkg_verbose_@@AM_AM_DEFAULT_VERBOSITY@@)
pkg_verbose_0 = @@echo PKG-GEN $@@;
foo: foo.in
diff --git a/m4/silent.m4 b/m4/silent.m4
index 6d2a1a2..1928feb 100644
--- a/m4/silent.m4
+++ b/m4/silent.m4
@@ -1,11 +1,11 @@
## -*- Autoconf -*-
-# Copyright (C) 2009 Free Software Foundation, Inc.
+# Copyright (C) 2009, 2011 Free Software Foundation, Inc.
#
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
-# serial 1
+# serial 2
# AM_SILENT_RULES([DEFAULT])
# --------------------------
@@ -20,6 +20,35 @@ yes) AM_DEFAULT_VERBOSITY=0;;
no) AM_DEFAULT_VERBOSITY=1;;
*) AM_DEFAULT_VERBOSITY=m4_if([$1], [yes], [0], [1]);;
esac
+dnl
+dnl A few `make' implementations (e.g., NonStop OS and NextStep)
+dnl do not support nested variable expansions.
+dnl See automake bug#9928 and bug#10237.
+am_make=${MAKE-make}
+AC_CACHE_CHECK([whether $am_make supports nested variables],
+ [am_cv_make_support_nested_variables],
+ [if AS_ECHO([['TRUE=$(BAR$(V))
+BAR0=false
+BAR1=true
+V=1
+am__doit:
+ @$(TRUE)
+.PHONY: am__doit']]) | $am_make -f - >/dev/null 2>&1; then
+ am_cv_make_support_nested_variables=yes
+else
+ am_cv_make_support_nested_variables=no
+fi])
+if test $am_cv_make_support_nested_variables = yes; then
+ AM_V='$(V)'dnl Using `$V' instead of `$(V)' breaks IRIX make.
+ AM_AM_DEFAULT_VERBOSITY='$(AM_DEFAULT_VERBOSITY)'
+else
+ AM_V=$AM_DEFAULT_VERBOSITY
+ AM_AM_DEFAULT_VERBOSITY=$AM_DEFAULT_VERBOSITY
+fi
+AC_SUBST([AM_V])dnl
+AM_SUBST_NOTMAKE([AM_V])dnl
+AC_SUBST([AM_AM_DEFAULT_VERBOSITY])dnl
+AM_SUBST_NOTMAKE([AM_AM_DEFAULT_VERBOSITY])dnl
AC_SUBST([AM_DEFAULT_VERBOSITY])dnl
AM_BACKSLASH='\'
AC_SUBST([AM_BACKSLASH])dnl
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 831906b..920d994 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -751,6 +751,7 @@ silent-many-gcc.test \
silent-many-generic.test \
silent-lex-gcc.test \
silent-lex-generic.test \
+silent-nested-vars.test \
silent-yacc-gcc.test \
silent-yacc-generic.test \
silent-configsite.test \
diff --git a/tests/Makefile.in b/tests/Makefile.in
index 3ad0146..470ed6c 100644
--- a/tests/Makefile.in
+++ b/tests/Makefile.in
@@ -1035,6 +1035,7 @@ silent-many-gcc.test \
silent-many-generic.test \
silent-lex-gcc.test \
silent-lex-generic.test \
+silent-nested-vars.test \
silent-yacc-gcc.test \
silent-yacc-generic.test \
silent-configsite.test \
diff --git a/tests/silent-nested-vars.test b/tests/silent-nested-vars.test
new file mode 100755
index 0000000..6716930
--- /dev/null
+++ b/tests/silent-nested-vars.test
@@ -0,0 +1,111 @@
+#!/bin/sh
+# Copyright (C) 2011 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 silent-rules mode, on 'make' implementations that do not
+# support nested variables.
+
+. ./defs || Exit 1
+
+set -e
+
+mkdir sub
+
+cat >>configure.in <<'EOF'
+AM_SILENT_RULES
+AC_CONFIG_FILES([sub/Makefile])
+AC_PROG_CC
+AM_PROG_CC_C_O
+AC_OUTPUT
+EOF
+
+cat > Makefile.am <<'EOF'
+# Need generic and non-generic rules.
+bin_PROGRAMS = foo bar
+bar_CFLAGS = $(AM_CFLAGS)
+SUBDIRS = sub
+EOF
+
+cat > sub/Makefile.am <<'EOF'
+AUTOMAKE_OPTIONS = subdir-objects
+# Need generic and non-generic rules.
+bin_PROGRAMS = baz bla
+bla_CFLAGS = $(AM_CFLAGS)
+EOF
+
+cat > foo.c <<'EOF'
+int main ()
+{
+ return 0;
+}
+EOF
+cp foo.c bar.c
+cp foo.c sub/baz.c
+cp foo.c sub/bla.c
+
+cat >mymake <<'EOF'
+#! /bin/sh
+makerules=
+
+case $1 in
+ -f)
+ makefile=$2
+ case $2 in
+ -) makerules=`cat` || exit ;;
+ esac ;;
+ *)
+ for makefile in makefile Makefile; do
+ test -f $makefile && break
+ done ;;
+esac
+
+if printf '%s\n' "$makerules" | LC_ALL=C grep '\$([a-zA-Z0-9_]*\$' $makefile
+then
+ echo >&2 "mymake: $makefile contains nested variables"
+ exit 1
+fi
+exec $mymake_MAKE "$@"
+EOF
+chmod a+x mymake
+mymake_MAKE=${MAKE-make}
+export mymake_MAKE
+
+$ACLOCAL
+$AUTOMAKE --add-missing
+$AUTOCONF
+
+./configure --enable-silent-rules MAKE=./mymake
+./mymake >stdout || { cat stdout; Exit 1; }
+cat stdout
+$EGREP ' (-c|-o)' stdout && Exit 1
+grep 'mv ' stdout && Exit 1
+grep 'CC .*foo\.' stdout
+grep 'CC .*bar\.' stdout
+grep 'CC .*baz\.' stdout
+grep 'CC .*bla\.' stdout
+grep 'CCLD .*foo' stdout
+grep 'CCLD .*bar' stdout
+grep 'CCLD .*baz' stdout
+grep 'CCLD .*bla' stdout
+
+./mymake clean
+./configure --disable-silent-rules MAKE=./mymake
+./mymake >stdout || { cat stdout; Exit 1; }
+cat stdout
+grep ' -c' stdout
+grep ' -o foo' stdout
+$EGREP '(CC|LD) ' stdout && Exit 1
+
+:
--
1.7.6.4
GNU bug tracking system
Copyright (C) 1999 Darren O. Benham,
1997,2003 nCipher Corporation Ltd,
1994-97 Ian Jackson.