1 GNU `m4' is an implementation of the traditional Unix macro
2 processor. It is mostly SVR4 compatible, although it has some
3 extensions (for example, handling more than 9 positional parameters
4 to macros). `m4' also has builtin functions for including files,
5 running shell commands, doing arithmetic, etc. Autoconf needs GNU
6 `m4' for generating `configure' scripts, but not for running them.
8 GNU `m4' has been originally written by Rene' Seindal, from Denmark.
10 GNU `m4' has a web site at http://www.gnu.org/software/m4/.
12 If GNU `m4' is meant to serve GNU `autoconf', beware that `m4'
13 should be fully installed *prior to* configuring `autoconf' itself.
14 Likewise, if you intend on hacking GNU `m4' from CVS, the bootstrap
15 process requires that you first install a released copy of GNU `m4'.
17 In the subdirectories `tests' and `examples' you will find various m4
18 files, ranging from trivial test files to rather advanced macros. If
19 you intend to use m4 seriously, you might find useful material down
22 See file `COPYING' for copying conditions.
23 See file `INSTALL' for compilation and installation instructions.
24 See file `ABOUT-NLS' for how to customize this program to your language.
25 See file `NEWS' for a list of major changes in the current release.
26 See file `AUTHORS' for the names of maintainers.
27 See file `THANKS' for a list of contributors.
29 By using `./configure --with-gmp, you get multiple precision integral
30 and rational arithmetic using mpeval. The implementation depends on the
33 By using `./configure --with-modules=`foo bar baz', you get an m4 with only
34 the named modules preloaded. The default modules (preloaded if you do not
35 use this option) are sufficient to do the job of GNU m4-1.4. Additional
36 modules may be desirable, or necessary if libltdl does not support your
37 host architecture. The implementation uses libltdl interface, details of
38 which are in the libtool manual. See file `modules/README' for a more
41 By using `./configure --with-dmalloc', GNU m4 is linked with Gray
42 Watson's dmalloc package. It is a debugging option for finding memory
43 management problems. Gray Watson's dmalloc package is available at
44 ftp://ftp.letters.com/src/dmalloc/dmalloc.tar.gz.
46 GNU M4 uses GNU Libtool in order to build shared libraries on a
47 variety of systems. While this is very nice for making usable
48 binaries, it can be a pain when trying to debug a program. For that
49 reason, compilation of shared libraries can be turned off by
50 specifying the `--disable-shared' option to `configure'.
52 Send bug reports, comments or ideas to `bug-m4@gnu.org'. A bug report
53 is an adequate description of the problem: your input, what you
54 expected, what you got, and why this is wrong. Diffs are welcome, but
55 they only describe a solution, from which the problem might be uneasy to
56 infer. Don't forget all relevant information about your operating
57 system, compiler, libraries, ...
59 The easiest way to remember this information is by using the
60 testsuite. Any test failures are automatically logged, along with
61 lots of useful information about your setup; simply mailing
62 tests/testsuite.log to `bug-m4@gnu.org' is a good start. If you want
63 to dive in and debug a failure, you may find it useful to fine-tune
64 the execution of the testsuite. For example, running test 12 in
65 verbose mode can be done with:
67 make check TESTSUITEFLAGS='-v -d -x 12'
69 The testsuite understands --help to tell you more about the current
77 If you wish to run bootstrap, the released versions of autoconf,
78 automake, and libtool are missing some functionality we need. You
79 will need a CVS build of libtool head (1.5.x does not have enough
80 functionality), and use the 2.59d snapshot of autoconf or a CVS
81 build. If you do not use a CVS build of automake, you can instead
82 patch automake-1.9.5 or 1.9.6 according to the patch below:
84 --- automake-1.9.5/automake.in.orig 2005-02-12 10:06:56.000000000 +0000
85 +++ automake-1.9.5/automake.in 2005-04-20 14:08:05.000000000 +0100
87 use Automake::RuleDef;
88 use Automake::Wrap 'makefile_wrap';
96 my $am_config_aux_dir = '';
98 +# Directory to search for AC_LIBSOURCE file, as set by AC_CONFIG_LIBOBJ_DIR
100 +my $config_libobj_dir = '';
102 # Whether AM_GNU_GETTEXT has been seen in configure.ac.
103 my $seen_gettext = 0;
104 # Whether AM_GNU_GETTEXT([external]) is used.
105 @@ -2067,7 +2072,7 @@
109 - require_file_with_macro ($cond, $var, FOREIGN, $iter);
110 + require_libobj_with_macro ($cond, $var, FOREIGN, $iter);
112 elsif ($iter ne 'alloca.c')
114 @@ -2079,7 +2084,7 @@
115 my $bs = var ('BUILT_SOURCES');
116 if (! $bs || ! grep (/$rewrite/, $bs->value_as_list_recursive))
118 - require_file_with_macro ($cond, $var, FOREIGN, $iter);
119 + require_libobj_with_macro ($cond, $var, FOREIGN, $iter);
123 @@ -2092,7 +2097,7 @@
125 $var->requires_variables ("\@${lt}ALLOCA\@ used", $lt . 'ALLOCA');
126 $dep_files{'$(DEPDIR)/alloca.P' . $myobjext} = 1;
127 - require_file_with_macro ($cond, $var, FOREIGN, 'alloca.c');
128 + require_libobj_with_macro ($cond, $var, FOREIGN, 'alloca.c');
129 &saw_extension ('c');
132 @@ -4636,6 +4641,7 @@
133 AC_CONFIG_AUX_DIR => 1,
134 AC_CONFIG_FILES => 1,
135 AC_CONFIG_HEADERS => 1,
136 + AC_CONFIG_LIBOBJ_DIR => 1,
137 AC_CONFIG_LINKS => 1,
140 @@ -4731,6 +4737,12 @@
141 push @config_headers, $spec;
144 + elsif ($macro eq 'AC_CONFIG_LIBOBJ_DIR')
146 + $config_libobj_dir = $args[1];
147 + $relative_dir = '.';
148 + check_directory ($config_libobj_dir, $where);
150 elsif ($macro eq 'AC_CONFIG_LINKS')
152 foreach my $spec (split (' ', $args[1]))
153 @@ -5761,6 +5773,15 @@
154 use constant IN_COMMENT => 2;
155 my $prev_state = IN_RULE_DEF;
157 + # Calculate the relative path from this Makefile to LIBOBJDIR.
158 + my $am_libobj_dir = '';
159 + unless ($config_libobj_dir eq '')
161 + my $dir = File::Spec->abs2rel ($config_libobj_dir, $relative_dir);
162 + $am_libobj_dir = "$dir/" unless $dir eq '';
164 + &define_variable ('LIBOBJDIR', "$am_libobj_dir", INTERNAL);
166 while ($_ = $am_file->getline)
168 $where->set ("$amfile:$.");
169 @@ -6975,6 +6996,22 @@
170 require_file ($macro->rdef ($cond)->location, $mystrict, @files);
173 +# &require_libobj_with_macro ($COND, $MACRO, $MYSTRICT, @FILES)
174 +# -------------------------------------------------------------
175 +sub require_libobj_with_macro ($$$@)
177 + my ($cond, $macro, $mystrict, @files) = @_;
178 + $macro = rvar ($macro) unless ref $macro;
179 + if ($config_libobj_dir eq '')
181 + require_file ($macro->rdef ($cond)->location, $mystrict, @files);
185 + require_file_internal ($macro->rdef ($cond)->location, $mystrict,
186 + $config_libobj_dir, @files);
190 # &require_conf_file ($WHERE, $MYSTRICT, @FILES)
191 # ----------------------------------------------