Zack Weinberg [Mon, 4 Jan 2021 22:27:37 +0000 (17:27 -0500)]
autoreconf: don’t error out when AM_GNU_GETTEXT is used alone.
Some projects intentionally don't call AM_GNU_GETTEXT_(REQUIRE_)VERSION
because they have all of the gettext infrastructure checked into version
control and they want autoreconf to _not_ run autopoint. Therefore, make
the “AM_GNU_GETTEXT is used, but not AM_GNU_GETTEXT_(REQUIRE_)VERSION”
and “AM_GNU_GETTEXT_(REQUIRE_)VERSION is used, but not AM_GNU_GETTEXT”
diagnostics be warnings again, as they were in 2.69.
(Technically these diagnostics were always errors, in the sense that
they were reported with a call to Autom4te::Channels::error(), but
prior to 2.70, error() calls made by autoreconf did not cause
autoreconf to exit unsuccessfully, due to an unrelated bug. So people
came to depend on these diagnostics not being fatal.)
Zack Weinberg [Tue, 29 Dec 2020 20:33:33 +0000 (15:33 -0500)]
autom4te: always update the output file, even if it hasn’t changed
Automake generates a Makefile rule for regenerating the configure
script, that relies on an invocation of ‘autoconf’ always bumping the
timestamp on the configure script, even if it hasn’t changed.
The patch to make autom4te update the output file atomically
(1725c947144d9bebfe7817c2c5f0d53d884b1297) broke this.
Fixes several failures in automake’s test suite.
* bin/autom4te.in (handle_output): Always call update_file with force=1.
* tests/tools.at (autoconf: timestamp changes): New test.
Zack Weinberg [Mon, 21 Dec 2020 19:04:22 +0000 (14:04 -0500)]
Restore compatibility with older std-gnu11.m4.
Gnulib’s std-gnu11.m4 backports C11 and C++11 detection to autoconf
2.69. It does this by replacing the definitions of AC_PROC_CC and
AC_PROG_CXX and most of their subroutines. In particular, it replaces
the definitions of _AC_PROG_CC_C11, _AC_PROG_CC_C99, and _AC_C_STD_TRY,
but it does *not* replace the definition of _AC_PROG_CC_C89.
Autoconf commit 131d8c69f31dc6fc8dc93abe1096d52d1fe19fd3 changed the
calling convention of _AC_C_STD_TRY, and changed the internal
definitions of _AC_PROG_CC_C{11,99,89} to match. If std-gnu11.m4 is
in use, our _AC_PROG_CC_C89 calls their _AC_C_STD_TRY with the new
calling convention, and this produces a syntactically invalid
configure script. (This is is fortunate: it could easily have been a
runtime malfunction that only manifested with compilers that only
implement C89, and then we might not have noticed the problem for
years.)
Gnulib commit a3b3fc85e3e632374811b27cb2111e50fa177e36 makes
std-gnu11.m4 do nothing when used with autoconf >=2.70, but older
versions of the file will circulate for years to come, so this patch
works around the problem in autoconf. It does this by renaming all of
the internal macros involved with C and C++ standard edition
detection, *except* _AC_PROG_CC_C89. AC_PROG_CC now calls
_AC_PROG_CC_STDC_EDITION, which loops over all supported editions
calling _AC_PROG_CC_STDC_EDITION_TRY, which uses the data provided by
the existing _AC_C_C${edition}_TEST_PROGRAM macros and a new set of
macros called _AC_C_C${edition}_OPTIONS to perform the test for that
edition of the standard. Similarly, AC_PROG_CXX calls
_AC_PROG_CXX_STDCXX_EDITION, which loops calling
_AC_PROG_CXX_STDCXX_EDITION_TRY, which uses data from
_AC_CXX_CXX${edition}_TEST_PROGRAM and _AC_CXX_CXX${edition}_OPTIONS.
_AC_PROG_CC_C89 is the only macro from the old set that we still
define, and its definition is reverted to what std-gnu11.m4 expects it
to be. Nothing in Autoconf proper uses it anymore.
foreign.at grows a test to verify that the compatibility stub version
of _AC_PROG_CC_C89 does its job. Since this is now the third test
involving an embedded copy of a third-party macro, I broke them all
out of foreign.at to separate files in test/data/.
In addition to fixing the breakage, this patch should make it easier
to extend C / C++ standard edition detection in the future, by getting
rid of the if-else chains in AC_PROG_CC/CXX and by disentangling the
lists of command-line options to test from the logic.
I also changed the manual to suggest people refer to the variables
‘ac_prog_cc_stdc’ and ‘ac_prog_cxx_stdcxx’ to learn which edition
of the C and C++ standards are selected; these are much easier to
work with than the ac_cv_prog_cc_cNN cache variables.
(_AC_PROG_CC_C89): Convert to compatibility stub for std-gnu11.m4.
(AC_PROG_CC): Use _AC_PROG_CC_STDC_EDITION.
(AC_PROG_CXX): Use _AC_PROG_CXX_STDCXX_EDITION.
* tests/data/ax_prog_cc_for_build_v18.m4
* tests/data/ax_prog_cxx_for_build_v3.m4
* tests/data/gnulib_std_gnu11_2020_08_17.m4: New files.
* tests/foreign.at (AX_PROG_CC_FOR_BUILD, AX_PROG_CXX_FOR_BUILD):
Remove embedded copy of ax_prog_cc_for_build_v18.m4,
ax_prog_cxx_for_build_v3.m4 respectively.
(gnulib-std-gnu11.m4): New test.
* tests/local.mk: Distribute tests/data/*.m4.
* doc/autoconf.texi (AC_PROG_CC, AC_PROG_CXX): Document use of
ac_prog_cc_stdc / ac_prog_cxx_stdcxx, respectively, to tell which
edition of the C / C++ standards are selected, instead of looking
through a series of cache variables with awkward definitions.
Zack Weinberg [Wed, 23 Dec 2020 17:14:06 +0000 (12:14 -0500)]
Use -fno-builtin, not -Werror, in AC_CHECK_DECLS (#110400)
clang issues only a warning, not an error, when an undeclared
identifier that names a built-in function is used: for instance
char *(*p)(const char *, int) = strchr;
(with no `#include <string.h>`) is an error with most compilers,
a warning with clang. This broke the 2.69 implementation of
AC_CHECK_DECL. In commit 82ef7805faffa151e724aa76c245ec590d174580,
we tried to work around this quirk by using -Werror, but that put us
at risk of being tripped up by other warnings. Bug 110400 reports,
for instance, that this fragment (which is roughly what you get, after
preprocessing, when AC_CHECK_DECL is applied to a function that *is*
properly declared)
extern void ac_decl (int, char *);
int main (void)
{
(void) ac_decl;
;
return 0;
}
provokes a warning from clang (and thus an error) when -Wextra-semi-stmt
has been added to CFLAGS earlier in the configure script. The extra
semicolon comes from AC_LANG_PROGRAM, and we can’t get rid of it
because we have no way of telling reliably when someone wrote
something like
with no semicolon at the end of the statement; this has been
acceptable for decades. Besides, that’s just one warning, who knows
what compilers will start complaining about tomorrow?
So: change AC_CHECK_DECL to compile its programs with -fno-builtin,
instead, when the default compilation mode fails to detect an
undeclared strchr. The code is restructured so that we can try other
options as well, if we find another compiler with the same quirk but
different command-line syntax.
(All of this logic is very C-family specific, but it appears to me
that AC_CHECK_DECL has never worked with other languages, so we can
continue to live with that for now.)
* lib/autoconf/general.m4 (_AC_UNDECLARED_WARNING): Rename to
_AC_UNDECLARED_BUILTIN. Instead of looking at diagnostic output,
loop trying to find a command-line option that makes the compiler
error out on undeclared builtins.
(_AC_CHECK_DECL_BODY): Don’t AC_REQUIRE anything here.
Make shell code language-agnostic, except for the actual test program.
Add arguments to the shell function for additional compiler options
to use.
(AC_CHECK_DECL): AC_REQUIRE _AC_UNDECLARED_BUILTIN here.
Supply $ac_{AC_LANG_ABBREV}_undeclared_builtin_options to
ac_fn_check_decl.
* tests/local.at (AT_CONFIG_CMP): Update list of variables to ignore
when comparing C and C++ configure runs.
* tests/semantics.at (AC_CHECK_DECLS): Add memcpy and strchr to
AC_CHECK_DECLS call for functions that may be known to the compiler.
* doc/autoconf.texi (AC_CHECK_DECL, AC_CHECK_DECLS): Remove note
about compiler warnings.
Zack Weinberg [Mon, 21 Dec 2020 20:29:32 +0000 (15:29 -0500)]
autom4te: correct error message when we can’t create autom4te.cache.
While testing something else, I noticed that autom4te may print a
nonsensical error message when it fails to create autom4te.cache,
because it checks again whether the directory already exists before
giving up, and this clobbers errno.
Instead of doing (the perl equivalent of)
test -d $cache || mkdir $cache || test -d $cache
call mkdir unconditionally. If it fails with an errno code other than
EEXIST, consider that a hard failure; if it fails with EEXIST, check
whether the thing that exists is in fact a directory. (A symlink to
a directory qualifies; I wouldn’t be surprised if people are moving
autom4te.cache around with symlinks.)
Either way, if we fail, report strerror(errno) from the original
mkdir failure. Also, print the current working directory as part
of the error message; this aids debugging when you’re working with a
big hairy nested tree.
* bin/autom4te.in: Don’t check whether autom4te.cache exists before
attempting to create it. Only stat autom4te.cache if mkdir fails
with EEXIST, otherwise fail immediately. Make sure to report the
errno code from mkdir, not the subsequent stat (if any). Report
the current working directory as part of the error message.
* tests/tools.at: Verify that autom4te reports the actual reason when
it fails to create autom4te.cache. Verify that failure to create
autom4te.cache because that name exists, but isn’t a directory,
is detected.
Paul Eggert [Fri, 11 Dec 2020 23:18:41 +0000 (15:18 -0800)]
Port minor AC_FUNC_ALLOCA fixes from Gnulib
* lib/autoconf/functions.m4 (_AC_LIBOBJ_ALLOCA, AC_FUNC_ALLOCA):
Use ' not ` in generated comments, as per current GNU coding style.
(_AC_LIBOBJ_ALLOCA): Use plain # instead of unnecessary quadrigraph.
This patch is adapted from Gnulib.
Paul Eggert [Fri, 11 Dec 2020 23:15:28 +0000 (15:15 -0800)]
Improve port of AC_C_RESTRICT to Oracle C++
Problem reported by Christian Biesinger in:
https://lists.gnu.org/r/bug-gnulib/2019-12/msg00159.html
* lib/autoconf/c.m4 (AC_C_RESTRICT): Port better to
Oracle Developer Studio C++ 12.5 or later.
This patch is adapted from Gnulib.
Zack Weinberg [Tue, 8 Dec 2020 16:14:19 +0000 (11:14 -0500)]
testsuite: log version of M4 and Perl
Jannick reported problems on OSX for which the most plausible
explanation is that the system-provided M4 is emitting error messages
with different line numbers than we expect, perhaps because Apple
froze their copy of GNU M4 to the last GPLv2 release. To test this
hypothesis, add $PERL and $M4 to AT_TESTED in our testsuite.
* tests/atlocal.in: Also set $M4 from configure.
* tests/local.at: Add AT_TESTED([$PERL $M4]).
Zack Weinberg [Tue, 8 Dec 2020 16:12:04 +0000 (11:12 -0500)]
lib/autotest/general.m4: typo fix
The absolute-path case in AT_TESTED had a typo in it, causing bizarre
error messages and preventing programs identified by absolute path
from being logged properly.
* lib/autotest/general.m4 (AT_TESTED): Fix typoed shell syntax in
handling of programs identified by absolute path.
Zack Weinberg [Tue, 8 Dec 2020 15:36:28 +0000 (10:36 -0500)]
Three minor testsuite fixes.
1. To insulate the test suite from a system-provided config.site file,
set the CONFIG_SITE environment variable to a file that is known not
to exist. Problem reported by Jannick.
2. AC_PROG_CC, AC_PROG_CXX, AC_PROG_CPP, and AC_PROG_CXXCPP may set
cache variables named ‘ac_cv_prog_$tool’ or ‘ac_cv_prog_ac_ct_$tool’,
depending on system conditions; _AT_CONFIG_CMP_PRUNE needs to handle
both possibilities. Found by testing on FreeBSD 12; I have no idea
why it didn’t show up on _any_ of my other test platforms.
3. The ‘AC_PROG_LEX with yywrap’ test needs to be skipped on systems
that don’t provide libl.a nor libfl.a. This change needed yet another
hook for AT_CHECK_MACRO. Found by testing on Alpine Linux.
(Ideally, instead of skipping this test, we would test that this
configure script *errors out* on these systems, but that would involve
much more invasive changes to AT_CHECK_MACRO, which I don’t want to
hold the release for.)
* tests/local.at (AT_PREPARE_TESTS): Set CONFIG_SITE to refer to
a file that is known not to exist, and export it.
(_AT_CONFIG_CMP_PRUNE): Prune all variables matching the
ERE ‘ac_cv_prog_(ac_ct_)?(CC|CXX|CPP|CXXCPP)’.
(AT_CHECK_MACRO): Add PRETEST-CMDS argument which takes commands to
execute immediately after AT_SETUP.
* tests/semantics.at (AC_PROG_LEX with yywrap): Using PRETEST-CMDS,
skip this test on OSes where neither -ll nor -lfl provides a
definition of yywrap.
Zack Weinberg [Tue, 8 Dec 2020 15:32:04 +0000 (10:32 -0500)]
autoreconf --install --force: replace install-sh with no timestamp
Old versions of install-sh did not have a timestamp line. Therefore,
treat the absence of a timestamp line as indicating a very old file
(that --install --force should replace), not as an error.
Problem reported by Pascal Terjan.
* bin/autoreconf.in (extract_time_stamp): Return 1970-01-01 when
no timestamp line is found.
* tests/torture.at (Missing auxiliary files (--force)):
Test replacement of old install-sh with no timestamp line.
Zack Weinberg [Mon, 7 Dec 2020 22:17:40 +0000 (17:17 -0500)]
Update documentation of AC_USE_SYSTEM_EXTENSIONS.
The list of macros documented as being defined by
AC_USE_SYSTEM_EXTENSIONS had gotten out of sync with the actual list.
Update it thoroughly.
Also, I introduced an error into the commentary when I merged Julien
ÉLIE’s patch to define _NETBSD_SOURCE and _OPENBSD_SOURCE in
AC_USE_SYSTEM_EXTENSIONS. _OPENBSD_SOURCE does something on NetBSD
and *doesn’t* do anything on OpenBSD. This is corrected.
Clean up the code in AC_USE_SYSTEM_EXTENSIONS a bit while I’m in
there; we now had a redundant definition of _NETBSD_SOURCE (one
unconditional and one conditional on minix/config.h existing).
Reorganize the macro to make it easier to catch problems like this in
the future.
* lib/autoconf/specific.m4 (AC_USE_SYSTEM_EXTENSIONS): Reorganize;
remove redundant AC_DEFINE of _NETBSD_SOURCE; add some missing
AC_BEFOREs; use _AC_CHECK_HEADER_ONCE for header checks;
revise all commentary.
* doc/autoconf.texi (AC_USE_SYSTEM_EXTENSIONS): Update.
Zack Weinberg [Mon, 7 Dec 2020 16:53:06 +0000 (11:53 -0500)]
Revise documentation of AC_PROG_CC and comments on conformance checks.
Makes the documentation of AC_PROG_CC consistent with the
documentation of AC_PROG_CXX. Also removes a bunch of redundant text
from c.m4 and adds lists of the headers that *can* be used in the
conformance tests, so future hackers don’t have to look them up.
* doc/autoconf.texi (AC_PROG_CC): Make description consistent with
description of AC_PROG_CXX.
* lib/autoconf/c.m4: Clean up some outdated or repetitive commentary
and add lists of the freestanding headers above the code that needs
to avoid using non-freestanding headers.
Zack Weinberg [Mon, 7 Dec 2020 16:49:52 +0000 (11:49 -0500)]
Add checks of __STDC__ and __STDC_VERSION__ to C conformance tests.
This makes the C conformance tests more consistent with the C++
conformance tests, and should also speed up cycling through the
possible options to turn on C99/C11.
Tested with gcc, clang, SunPRO C, and AIX xlc.
* lib/autoconf/c.m4 (_AC_C_C89_TEST_GLOBALS): Add preprocessor test
for __STDC__ being defined (to any value).
(_AC_C_C99_TEST_GLOBALS, _AC_C_C11_TEST_GLOBALS): Add preprocessor
test of the value of __STDC_VERSION__.
Zack Weinberg [Mon, 7 Dec 2020 16:32:55 +0000 (11:32 -0500)]
autom4te: don’t crash when warnings have no stacktrace
In testing on Darwin (OSX), sometimes warnings reported from M4 code
reach autom4te with no stack trace at all, causing the perl script to
crash with a “use of uninitialized value” error. The root cause of
the problem is not clear to me, but the script certainly shouldn’t
crash.
Problem found by Jannick <thirdedition@gmx.net>.
* bin/autom4te.in: When processing warnings, make sure $stacktrace is
defined.
Jannick [Mon, 7 Dec 2020 16:28:57 +0000 (11:28 -0500)]
Small bug fixes for the test suite.
* tests/atlocal.in: Also set AWK to value detected by configure.
Alphabetize list of shell variables set by config.status.
* tests/local.mk: Add a rule to recreate tests/atconfig when
config.status changes.
Zack Weinberg [Sun, 6 Dec 2020 17:23:41 +0000 (12:23 -0500)]
Don’t use hosted headers when testing for C(++) standard level (#110393)
The tests for the level of the C and C++ standard supported by their
respective compilers should also avoid using any headers that are not
guaranteed to be available in the respective freestanding environment.
Unlike the previous change, the only user-visible consequence of this
one should be that C11/C99/C89/C++11/C++98 *compiler* support is now
correctly detected when the compilation target is a freestanding
environment.
This patch also refactors how we “emit [the text of the C/C++
standard-conformance test programs] only once per [configure script],
into shell variables which can then be referenced repeatedly,” from c3853873, because editing them just a little made the M4 quotation
break. Clearly too fragile.
I believe this completes the fix for bug #110393.
* lib/autoconf/c.m4 (_AC_PROG_CC_C89, _AC_PROG_CC_C99, _AC_PROG_CC_C11)
_AC_C_C99_TEST_HEADER, _AC_C_C99_TEST_BODY): Move all test program
fragments into new macros that can be AC_REQUIREd individually:
_AC_C_C89_TEST_GLOBALS, _AC_C_C89_TEST_MAIN, _AC_C_C89_TEST_PROGRAM,
_AC_C_C99_TEST_GLOBALS, _AC_C_C99_TEST_MAIN, _AC_C_C99_TEST_PROGRAM,
_AC_C_C11_TEST_GLOBALS, _AC_C_C11_TEST_MAIN, _AC_C_C11_TEST_PROGRAM.
Each emits test code at most once, into a shell variable in the
INIT_PREPARE diversion.
Revise each test program to use only library features of the
respective standard’s freestanding environment.
(_AC_C_STD_TRY): Take the *name* of the shell variable holding the
complete test program as an argument, not the code itself. All
callers adjusted to match.
Zack Weinberg [Sun, 6 Dec 2020 16:40:39 +0000 (11:40 -0500)]
AC_INCLUDES_DEFAULT: Check for presence of C90 hosted headers (#110393)
Since 1993, Autoconf has been assuming that it is safe to include any
of the headers defined by ISO C90 without checking for them; this is
inaccurate, since only a subset are necessarily available in a
C90 *freestanding* environment.
It is OK to assume the presence of a header in a macro that checks
specifically for something declared by that header (if the header is
not present, we will think the specific declaration is unavailable,
which is probably accurate for modern embedded environments). It is
also OK to continue recommending that user code use these headers
unconditionally—anyone working with a freestanding environment knows
it. But it is not OK for very generic code within Autoconf itself,
such as AC_INCLUDES_DEFAULT, to make this assumption.
Note that the set of headers that are not always available includes
stdio.h, which we have been assuming can be included unconditionally
for even longer.
In AC_INCLUDES_DEFAULT, revert to checking for string.h and stdlib.h
before including them. Also revert to defining STDC_HEADERS only when
string.h and stdlib.h are available (but do not check for float.h and
stdarg.h, as these are part of the freestanding set). Add a new check
for stdio.h. Sort the inclusion list by standard (C90 freestanding;
C90 hosted; C99; POSIX) and alphabetically within each group. Revise
all the documentation and update the testsuite.
* lib/autoconf/headers.m4 (AC_CHECK_INCLUDES_DEFAULT): Check for
stdio.h, stdlib.h, and string.h before including them. Define
STDC_HEADERS only when string.h and stdlib.h are both available.
Organize includes list by standard, then alphabetically.
* doc/autoconf.texi, NEWS: Update to match.
* tests/local.at (AT_CHECK_DEFINES): Make regexes more specific.
Also expect a definition of HAVE_STDIO_H.
* tests/c.at, tests/semantics.at, tests/tools.at: Use <float.h>,
not <stdio.h>, as a header that we expect always to exist.
Add HAVE_STDIO_H to various lists of macros that are expected to
appear in config.h.
Julien ÉLIE [Sun, 6 Dec 2020 15:45:35 +0000 (10:45 -0500)]
Define _NETBSD_SOURCE and _OPENBSD_SOURCE in AC_USE_SYSTEM_EXTENSIONS (#110392)
These expose additional extensions specific to those operating
systems, similar to _DARWIN_C_SOURCE, _GNU_SOURCE, etc.
(DragonflyBSD and FreeBSD currently do not have any equivalent
macros.)
Fixes bug #110392. See also
https://git.savannah.gnu.org/cgit/gnulib.git/tree/m4/extensions.m4
https://git.eyrie.org/?p=devel/rra-c-util.git;a=commitdiff;h=f8a922cf31804dcc25ac176dcc22fdcdffcb5fdf
* lib/autoconf/specific.m4 (AC_USE_SYSTEM_EXTENSIONS): Also define
_NETBSD_SOURCE and _OPENBSD_SOURCE. Add comment explaining that
there are (currently) no equivalent macros on DragonflyBSD and
FreeBSD. Put macro list in alphabetical order.
Zack Weinberg [Fri, 4 Dec 2020 21:32:35 +0000 (16:32 -0500)]
Revert "AC_PROG_CC: define via AC_DEFUN_ONCE". (#110350)
Revert commit 18c140b50b0619454d4da50d58a318cc257d580a, restoring
AC_PROG_CC to being defined as an ordinary AC_DEFUN. This broke
third-party macros (e.g. the Autoconf Macro Archive’s
AX_PROG_CC_FOR_BUILD) that intentionally invoked AC_PROG_CC a second
time with its guts redefined via a whole bunch of ‘pushdef’s. I don’t
think we want to support this long-term, but needing access to a
build-native compiler in cross-compilation is common enough that we
should have *some* supported way to do it, and it may as well be
AX_PROG_CC_FOR_BUILD until we come up with something better.
If we go back to AC_DEFUN_ONCE for AC_PROG_CC in the future, we should
do it consistently for all the “find me a compiler” macros -- it
was *only* done for AC_PROG_CC in 18c140b5.
The rationale for AC_DEFUN_ONCE seems to have been to reduce the size
of the generated configure script. The bulk of the size accountable to
AC_PROG_CC is the test programs for figuring out which version of the
C standard is available, so I tweaked _AC_C_STD_TRY (and _AC_CXX_STD_TRY)
to emit that text only once per program, into shell variables which
can then be referenced repeatedly.
Fixes bug #110350.
* NEWS, doc/autoconf.texi: Revert documentation changes associated
with AC_PROG_CC being a one-shot macro.
* lib/autoconf/c.m4 (AC_PROG_CC): Revert to defining with AC_DEFUN.
(_AC_C_STD_TRY, _AC_CXX_STD_TRY): Emit the test program only once,
even if invoked multiple times with the same arguments.
* tests/foreign.at (AX_PROG_CC_FOR_BUILD, AX_PROG_CXX_FOR_BUILD):
New tests.
Zack Weinberg [Wed, 28 Oct 2020 21:04:22 +0000 (17:04 -0400)]
Autotest: add official way to execute code before all/each test.
Currently, there isn’t any documented way for an Autotest testsuite to
add custom code to be run either right before the main driver loop, or
at the point of each AT_SETUP. For instance, there’s no good place to
put environment variable sanitization that should apply to the entire
testsuite (but isn’t universally relevant), or shell function
definitions to be used by custom test macros.
Autoconf’s test suite is poking shell functions directly into the
PREPARE_TESTS diversion, and doing environment variable sanitization
in each individual test. Both of these are obviously undesirable.
This patch adds three new AT_* macros that can be used to do these
things in an officially-supported way: AT_PREPARE_TESTS adds code to
be run right before the main driver loop, AT_PREPARE_EACH_TEST adds
code to be run at the beginning of each test, and AT_TEST_HELPER_FN
defines a shell function that will be available to each test. In
Autoconf’s test suite, I use AT_PREPARE_TESTS to factor out
environment variable sanitization that *ought* to apply across the
board, and AT_TEST_HELPER_FN for the helper function used by
AT_CHECK_ENV.
(This fixes the testsuite bug reported by Jannick at
https://lists.gnu.org/archive/html/autoconf/2020-10/msg00052.html :
CONFIG_SITE in the parent environment will no longer be visible to tests.)
It would be nice to give an example of when AT_PREPARE_EACH_TEST is
useful, in the documentation, but I didn’t find one in the autoconf
test suite.
* lib/autotest/general.m4 (AT_PREPARE_TESTS, AT_PREPARE_EACH_TEST)
(AT_TEST_HELPER_FN): New macros.
(AT_INIT, AT_TESTED): Emit the code to report tested programs only
if it’s needed, and make sure it’s after any code added by
AT_PREPARE_TESTS.
* tests/local.at: Add AT_PREPARE_TESTS block that ensures
$MAKE is set sensibly and $MAKEFLAGS and $CONFIG_SITE are unset.
Use AT_TEST_HELPER_FN for the helper function needed by AT_CHECK_ENV.
(AT_CHECK_MAKE): No need to sanitize $MAKE or $MAKEFLAGS here.
* tests/base.at, tests/compile.at, tests/m4sh.at, tests/torture.at:
No need to unset or neutralize $CONFIG_SITE in individual tests.
* tests/autotest.at: Add tests for new macros.
Bruno Haible [Tue, 1 Dec 2020 21:42:17 +0000 (22:42 +0100)]
Document better where to put -m32 or -m64 compiler options.
* doc/autoconf.texi (Preset Output Variables): Clarify that options -m32 or -m64
must go into CC, not CFLAGS and not CPPFLAGS either. This is needed because on
bi-arch platforms, config.guess runs $CC without $CFLAGS nor $CPPFLAGS.
Zack Weinberg [Mon, 30 Nov 2020 23:06:26 +0000 (18:06 -0500)]
Make autoreconf --force --install overwrite existing files (#110371)
The new feature of autoreconf --install installing config.guess,
config.sub, and install-sh itself didn’t implement --force mode
correctly; existing files would not be overwritten.
The fix has two parts. If --force is in effect, we try to install
everything that we can from the needed-auxfiles list *before* checking
which of them already exist. But also, we don’t overwrite existing
files unconditionally, even with --force; we only do so if the file we
can install has a newer “timestamp” line than the copy at the
destination. This is because Automake can also install all of the
files we can install. Suppose someone is using autoconf 2.70 with a
newly released automake 1.17; automake 1.17 will presumably ship with
a newer config.guess than autoconf 2.70 did; that version should win.
Fixes bug #110371.
* bin/autoreconf.in (extract_time_stamp, our_aux_file_is_newer): New functions.
(install_aux_file): If the destination exists, and our copy is not
newer, do not overwrite it.
(autoreconf_current_directory): When $force is true, attempt to
install all needed aux files *before* scanning for missing aux files.
(throughout): Remove extra \n from various error messages.
* tests/torture.at (Missing auxiliary files (--force)): New test.
Zack Weinberg [Wed, 14 Oct 2020 15:21:30 +0000 (11:21 -0400)]
AT_CHECK_MACRO: test C++ as well as C, cross as well as native
Many of the reported regressions in Autoconf 2.70 betas went unnoticed
for years because Autoconf’s bundled test suite didn’t test most of
the macros with a C++ compiler and/or in cross compilation mode.
There’s a special makefile target ‘maintainer-check-c++’ that runs all
the tests with CC=g++, but that doesn’t catch the regressions either,
because it doesn’t compare the configure results with what you’d have
gotten with a C compiler. Also, C and C++ have diverged to the point
where setting CC to a C++ compiler doesn’t work reliably anymore.
This patch overhauls AT_CHECK_MACRO to test each macro four times:
(C compiler, C++ compiler) x (native mode, cross-compilation mode).
All four tests are expected to produce the same config.cache and
config.h, except for certain predictable differences due to running
AC_PROG_CXX instead of AC_PROG_CC, and a short list of known,
acceptable differences, maintained in mktests.pl.
There are two classes of known, acceptable differences. Macros that
use AC_RUN_IFELSE aren’t tested in cross-compilation mode at all,
because they may crash the script (this is temporary and will be
revisited after 2.70). Macros that correctly detect a difference
between C and C++ (e.g. AC_HEADER_STDBOOL will notice that C++ doesn’t
have the _Bool type) are annotated with the specific cache variable
and #define that varies.
mktests.pl now also has the capability to provide values for the
MACRO-USE, ADDITIONAL-COMMANDS, and AUTOCONF-FLAGS arguments to
AT_CHECK_(AU_)MACRO, on a per-macro basis, but that’s not used in this
patch.
Some of the manual uses of AT_CHECK_MACRO do not need to test C++
and/or cross compilation; for them, there is a new test helper,
AT_CHECK_CONFIGURE_AC. Another new helper, AT_PRESERVE_CONFIG_STATUS,
is used extensively in AT_CHECK_(AU_)MACRO but may be also useful in
manual tests that need to do multiple configure runs.
This change supersedes AT_CHECK_MACRO_CROSS and
‘make maintainer-check-c++’, which are removed.
In my testing, setting CC to a C++ compiler no longer works at all,
for reasons that are impractical to fix (e.g. C++ compilers choke on
the test for C2011 features) so I have added a note to NEWS saying
that this is not supported anymore.
* tests/local.at (AT_CHECK_MACRO): Default behavior is now to test
the macro in both native and cross-compilation mode, and expect the
results to be identical. If the macro transitively required
AC_PROG_CC, and a C++ compiler is available, then test it twice
more with AC_LANG([C++]) in effect, and again expect the results to
be identical. New fifth argument TEST-PARAMETERS can modify this
behavior.
(_AT_FILTER_CXX_CV_VARIES, _AT_FILTER_CXX_DEFINE_VARIES): New,
subroutines of AT_CHECK_MACRO.
(AT_CHECK_MACRO_CROSS): Remove, subsumed by new AT_CHECK_MACRO
behavior.
(AT_CHECK_AU_MACRO): Forward to AT_CHECK_MACRO for the basic test;
then do the same autoupdate test as before, as a separate test group.
(at_check_env): Also ignore OPENMP_CXXFLAGS.
(AT_CONFIG_CMP): Add third argument EXTRA-VARIANCE that specifies
additional variables that are expected to vary in a particular test.
(_AT_CONFIG_CMP_PRUNE): New, subroutine of AT_CONFIG_CMP.
(AT_DEFINES_CMP): New helper macro that compares config.h headers,
with the ability to ignore variation in specific defines.
(_AT_DEFINES_CMP_PRUNE): New, subroutine of AT_DEFINES_CMP.
(AT_PRESERVE_CONFIG_STATUS): New helper that makes copies of
config.h, config.log, config.status, and state-env.after under
names that won’t be clobbered by a subsequent run of configure.
(AT_CHECK_CONFIGURE_AC): New helper that defines a complete test
group consisting of a single invocation of _AT_CHECK_AC_MACRO;
effectively what AT_CHECK_MACRO used to be.
(_AT_CHECK_AC_MACRO): Correct documentation comment; the PRE-TESTS
argument has always been optional.
* tests/mktests.pl (test_parameters): New global data object giving
extra arguments to pass to AT_CHECK_MACRO/AT_CHECK_AU_MACRO on a
per-macro basis.
(emit_test): New function that handles emitting calls to
AT_CHECK_(AU_)MACRO with the desired arguments.
(scan_m4_files): Use emit_test.
(au_exclude_list): Add AC_HAVE_LIBRARY, AC_COMPILE_CHECK,
AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK, and AC_TRY_RUN.
* tests/semantics.at (AC_CHECK_LIB, AC_SEARCH_LIBS): Rewrite test
using symbols from zlib instead of libm, to get consistent behavior
from C and C++.
(AC_SEARCH_LIBS (none needed)): Revise to clarify what is being tested.
(AC_CHECK_DECLS): Use _AC_LANG_ABBREV when inspecting cache variables.
(AC_CHECK_ALIGNOF, AC_CHECK_ALIGNOF struct)
(AC_CHECK_SIZEOF, AC_CHECK_SIZEOF struct)
No need for AT_CHECK_MACRO_CROSS.
(AC_CHECK_FILES): Switch to AT_CHECK_CONFIGURE_AC.
(AC_SYS_RESTARTABLE_SYSCALLS, AC_FUNC_WAIT3): Do not test in cross
compilation mode.
(AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK, AC_TRY_RUN)
(AC_COMPILE_CHECK, AC_HAVE_LIBRARY): New manual AT_CHECK_AU_MACRO tests.
* tests/c.at (Extensions, C keywords, AC_PROG_CPP requires AC_PROG_CC)
(AC_NO_EXECUTABLES (working linker), AC_NO_EXECUTABLES (broken linker)):
Switch to AT_CHECK_CONFIGURE_AC. Also convert case statements to AS_CASE.
(Broken/missing compilers): Pass CC=no-such-compiler on the command
line instead of hardwiring it in the configure script.
* tests/local.mk (maintainer-check-c++): Remove target.
(maintainer-check): Run the ordinary ‘make check’ as well as
‘make maintainer-check-posix’.
Zack Weinberg [Sat, 10 Oct 2020 19:47:01 +0000 (15:47 -0400)]
Rewrite mktests.sh in Perl.
This is probably marginally faster since it doesn’t have to read the
.m4 files twice or muck around with temporary files and subprocesses,
but the actual point of this rewrite is that it will make it easier to
provide additional arguments to AT_CHECK_MACRO and AT_CHECK_AU_MACRO
on a per-macro basis; this capability will be added and used in the
next patch.
In *this* patch, the ac*.at files are not functionally changed at all.
(The comments come out slightly differently, though.)
* tests/mktests.sh: Delete and...
* tests/mktests.pl: ...rewrite in Perl.
* tests/local.mk: Update to match.
Zack Weinberg [Wed, 7 Oct 2020 19:45:57 +0000 (15:45 -0400)]
Overhaul Erlang support.
Erlang is similar to Java in that it doesn’t compile to standalone
machine code; the output of ‘erlc’ is byte-code files that are then
interpreted by ‘erl’. We handle this poorly in a whole bunch of ways,
particularly when cross-compiling. This patch fixes up the more
serious problems:
- AC_COMPILE_IFELSE now actually works when AC_LANG([Erlang]) is in
effect.
- ‘conftest.beam’ is now deleted in several more places where it
could be created.
- The various AC_ERLANG_* macros that interrogate the runtime
environment do so by invoking ‘$ERL’ directly, rather than using
AC_RUN_IFELSE, and thus do not crash the configure script when
we think we’re cross-compiling. (It is not clear to me whether
they get the correct answer when cross-compiling, but this should
still be strictly an improvement.)
- The Erlang-related tests have been streamlined.
Further improvements are definitely possible, but we’d have to teach
the infrastructure to make $ac_objext language-specific first, which
seems like too big of a change for 2.70.
(This patch is all fallout from a logically unrelated testsuite change
which is coming up next. Gotta love the fundamental interconnectedness
of things.)
* lib/autoconf/general.m4 (_AC_COMPILE_IFELSE_BODY)
(_AC_LINK_IFELSE_BODY): Delete conftest.beam as well as conftest.$ac_objext.
* lib/autoconf/erlang.m4 (AC_ERLANG_PATH_ERLC, AC_ERLANG_PATH_ERL):
Don’t repeat work done by AC_PATH_TOOL.
(Erlang $ac_compile): Fake an .o file so AC_TRY_COMPILE will be happy.
(AC_LANG_COMPILER(Erlang)): AC_REQUIRE AC_ERLANG_NEED_ERLC, not
AC_ERLANG_PATH_ERLC. Also AC_REQUIRE AC_ERLANG_NEED_ERL so
AC_RUN_IFELSE works reliably.
(AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR)
(AC_ERLANG_SUBST_LIB_DIR, AC_ERLANG_SUBST_ERTS_VER):
Use $ERL -eval, not AC_RUN_IFELSE.
No need to AC_REQUIRE AC_ERLANG_NEED_ERLC.
* tests/erlang.at: Don’t test anything here that’s tested adequately
by acerlang.at; document which macros those are expected to be.
Remove unnecessary AC_ERLANG_PATH_ERL/ERLC invocations throughout.
(AT_CHECK_MACRO([Erlang])): Rename test to ‘Erlang basic compilation’;
expect both AC_COMPILE_IFELSE and AC_RUN_IFELSE to work;
handle cross compilation mode properly.
* tests/mktests.sh: Exclude from acerlang.at all macros completely
covered by erlang.at.
Zack Weinberg [Mon, 30 Nov 2020 14:26:37 +0000 (09:26 -0500)]
Make “redefining AS_ECHO internals” test more robust.
M4-redefining ‘printf’ as ‘echo’ brings back all the variations in
‘echo’ behavior that we were trying to get away from by switching to
‘printf’ in the first place. This caused a spurious failure on AIX.
* tests/m4sh.at (Redefining AS_ECHO internals): Redefine ‘printf’ as
a shell function with fully predictable output, not as ‘echo’.
Zack Weinberg [Sat, 28 Nov 2020 16:18:05 +0000 (11:18 -0500)]
torture.at: Insulate more tests from buggy third-party m4 files.
All tests that run autoreconf need to defend against the possibility
of aclocal not existing and/or barfing on bugs in third-party m4 files
installed on the build system. Two of the “Missing auxiliary files”
tests were missing this defensive code.
Zack Weinberg [Mon, 30 Nov 2020 16:26:06 +0000 (11:26 -0500)]
Avoid ‘new File::Temp’ in Perl scripts.
Despite what the documentation says, ‘new File::Temp’ does not work
reliably in perl 5.6.x. Rather than figure out exactly what is wrong
with it, let’s just stick to ‘tempfile’.
* bin/autom4te.in (handle_output): Use tempfile function instead of
object-oriented File::Temp interface.
* bin/autoreconf.in (install_aux_file): Likewise.
Zack Weinberg [Sat, 28 Nov 2020 16:08:28 +0000 (11:08 -0500)]
Disentangle HAVE__BOOL from ac_cv_header_stdbool_h.
AC_CHECK_HEADER_STDBOOL is documented to make two checks: whether the
C99 header <stdbool.h> is available and fulfills its
specification (i.e. including it makes the type ‘bool’ and the
constants ‘true’ and ‘false’ available), and, independently, whether
the type ‘_Bool’ is available.
In C++, the type ‘_Bool’ is usually _not_ available, but <stdbool.h>
is still supposed to be include-able and the type ‘bool’ and the
constants ‘true’ and ‘false’ are still supposed to be available
(unconditionally). However, the test for <stdbool.h> fulfilling its
specification freely used _Bool, and would therefore fail spuriously.
Correct this by checking for _Bool first, and then refactoring the
test program for <stdbool.h> so that it does all its tests using bool,
then repeats them with _Bool only when available.
* lib/autoconf/headers.m4 (AC_CHECK_HEADER_STDBOOL): Do the test for
_Bool before the test for stdbool.h. Test semantics of bool
unconditionally; test _Bool only when HAVE__BOOL is defined.
Zack Weinberg [Sat, 28 Nov 2020 15:01:31 +0000 (10:01 -0500)]
AC_FUNC_SETPGRP: Don’t depend on the return type of setpgrp.
AC_FUNC_SETPGRP determines whether you have the historic BSD setpgrp,
which takes two arguments and returns int, or the historic POSIX
setpgrp, which takes no arguments and returns int. Solaris has yet a
third variant, which takes no arguments and returns a pid_t (the new
process group ID). This difference causes AC_FUNC_SETPGRP’s test
program to fail to compile under AC_LANG([C++]), which in turn causes
the macro to report that setpgrp does take arguments, which is wrong.
It is not worth adding a new result #define for this variant,
since *all* forms of setpgrp are deprecated in favor of setpgid, which
is old enough that it can be used unconditionally. However, it is
worth documenting that this variant exists, and fixing AC_FUNC_SETPGRP
to produce the right value for its existing result #define on Solaris
with C++.
* lib/autoconf/functions.m4 (AC_FUNC_SETPGRP): Redesign test program to
not depend on the return type of setpgrp.
* doc/autoconf.texi (AC_FUNC_SETPGRP): Mention that the macro does not
check for the Solaris variant of setpgrp that returns pid_t. Change
programming advice to recommend use of setpgid.
Zack Weinberg [Mon, 30 Nov 2020 15:49:35 +0000 (10:49 -0500)]
AC_C_CHAR_UNSIGNED: Remove check of $GCC.
On systems where plain ‘char’ is unsigned (e.g. AIX) we would define
__CHAR_UNSIGNED__ only when $GCC was not true at configure time.
If AC_LANG([C++]) has been in effect since the beginning of the
script (so AC_PROG_CC was never invoked), $GCC will be false
regardless; this causes an inconsistency between the C and C++
behaviors, even when both compilers are GNU.
The point of checking $GCC here is that GCC has command line options
to override the signedness of plain ‘char’, and it predefines
__CHAR_UNSIGNED__ to indicate what the signedness actually is.
We don’t want config.h to override that. However, there is already
a special autoheader template for __CHAR_UNSIGNED__ that prevents it
being redefined if it’s defined already, so checking $GCC at
configure time is redundant and can safely be removed.
* lib/autoconf/c.m4 (AC_C_CHAR_UNSIGNED): Do not make result depend on
value of $GCC. Adjust commentary.
Zack Weinberg [Sat, 28 Nov 2020 17:22:09 +0000 (12:22 -0500)]
sc_error_message_uppercase: allow fully uppercased words
If an error message starts with an entire fully uppercased word,
that’s probably a proper noun and it should stay that way. For
instance, autoreconf has an error message that starts with
"AM_GNU_GETTEXT is used, but ..."; AM_GNU_GETTEXT is the name of an
Automake macro, it needs to stay uppercased.
This subsumes the existing exception for the words FATAL and WARNING.
While I was in there I generalized the exception for PRIuMAX to cover
all of the inttypes.h PRI* and SCN* macros.
This patch has been submitted to Gnulib; until it is merged there,
anyone running ‘make fetch’ should take care not to drop this change.
* maint.mk (sc_error_message_uppercase): Allow error messages that
begin with any fully uppercased word, or with any of the inttypes.h
PRI[dioux]\w+ or SCN[dioux]\w+ macros.
Zack Weinberg [Wed, 14 Oct 2020 22:03:21 +0000 (18:03 -0400)]
AC_INIT: better handling of unusual arguments (#110349)
Fix some subtle quotation bugs in _AC_INIT_PACKAGE that made it
impossible to put ‘,’ or an unbalanced close parenthesis in some of
the arguments to AC_INIT. Document that arguments to AC_INIT
containing parentheses, square brackets, ‘,’ or ‘#’ may need to be
double-quoted. Provide more detailed examples and exposition re
computing the arguments to AC_INIT when autoconf is run (e.g. with
git-version-gen). Add a whole bunch more tests for unusual arguments
to AC_INIT, and a test that the backward-compatibility behavior of
AC_INIT with only one argument is still correct.
This may still break some of the existing configure scripts described
in the threads at
https://lists.gnu.org/r/autoconf/2020-10/msg00013.html and
https://lists.gnu.org/r/bug-autoconf/2020-10/msg00012.html
but, I hope, only in ways covered by the existing warning in NEWS
about pickier M4 quotation.
* lib/autoconf/general.m4 (_AC_INIT_PACKAGE): Redo argument
normalization and default value selection in a simpler, less
error-prone fashion.
(_AC_INIT_PACKAGE_N): New helper subroutine.
(AC_INIT): Always call _AC_INIT_PACKAGE, but supply no arguments if
we were called with only one argument.
* tests/base.at (AC_INIT (obsolete invocation)): New test.
(AC_INIT with unusual version strings): Expand test.
Zack Weinberg [Mon, 16 Nov 2020 15:03:39 +0000 (10:03 -0500)]
AS_ECHO(_N): Do not expand macros named ‘s’ or ‘n’ (#110377)
AS_ECHO expands to ‘printf "%s\n" $1’. If a configure script defines
an M4 macro named ‘s’ or ‘n’ it will be expanded in the first argument
to printf, which is almost certainly not what was intended.
The configure script for ruby 2.7.2 uses ‘AS_VAR_PUSHDEF([s], ...)’
and breaks with 2.69d because of this.
Add some extra quoting so that the ‘%s\n’ is treated as literal;
similarly for AS_ECHO_N and the legacy shell variables $as_echo
and $as_echo_n.
For now, anyway, don’t quote the word ‘printf’; if someone does
define that as a M4 macro they might well mean to affect AS_ECHO.
(Whether this is something we *want* to allow, we can worry about
when it comes up.)
Fixes bug #110377.
* lib/m4sugar/m4sh.m4 (_AS_ECHO_N_PREPARE, AS_ECHO, AS_ECHO_N):
Add another layer of quoting around the first argument to printf.
* tests/m4sh.at (Redefining AS_ECHO internals): New test.
Zack Weinberg [Sun, 15 Nov 2020 19:27:38 +0000 (14:27 -0500)]
Don’t issue obsoletion warnings for AC_LANG_SAVE/RESTORE (#110375)
The most recently released version of libtool.m4 is five years old as
of this commit, and no new release is likely to appear anytime soon.
It uses AC_LANG_SAVE and AC_LANG_RESTORE, in a way that doesn’t
obviously translate to AC_LANG_PUSH and AC_LANG_POP. This will need
to be fixed by libtool upstream. Until that actually happens, disable
the -Wobsolete warnings for AC_LANG_SAVE and AC_LANG_RESTORE. (They
are still documented as obsolete in the manual, as they have been for
many years.)
Fixes bug #110375.
* lib/autoconf/lang.m4 (AC_LANG_SAVE, AC_LANG_RESTORE): Define with
AC_DEFUN, not AU_DEFUN; remove manual -Wobsolete warnings.
Zack Weinberg [Sun, 15 Nov 2020 18:56:18 +0000 (13:56 -0500)]
AS_IF: Handle else clause being empty after macro expansion (#110369)
AS_IF can emit a syntactically invalid shell if-then-else,
if CONDITION
then :
# ...
else
fi
when its IF-FALSE argument consists of macros that don’t produce any
shell code. This was a documented limitation in AS_IF, but it’s a bad
limitation to have, because macros that *used* to expand to shell
commands might start expanding to nothing in future releases. For
instance, this broke the libzmq configure script, which did
Perfectly valid in 2.69, but in 2.70 AC_PROG_CC_C99 doesn’t produce
any shell code and the script crashes.
We had that limitation for good reason: we can’t just put ‘:’ at the
beginning of the else-clause, like we do for the then-clause, because
that would clobber $? and the IF-FALSE commands might want to inspect
it. (This doesn’t matter for the then-clause, because $? is always
zero at the beginning of a then-clause anyway.) The simplest and
least inefficient shell construct I can find that works in this
context is a shell function that does ‘return $?’. Due to awkward
M4sh initialization ordering constraints (AS_IF gets used before we
can safely use shell functions) an indirection through a shell
variable is necessary. The structure of a m4sh script is now
#! /bin/sh
## M4sh Initialization
as_nop=:
...
## M4sh Shell Functions
as_fn_nop () { return $?; }
as_nop=as_fn_nop
...
and AS_IF emits
if CONDITION
then :
# ...
else $as_nop
# ...
fi
The uses of AS_IF that appear before the beginning of the M4sh Shell
Functions section are all under our control and they don’t need to
look at $?.
If anyone has a better idea for how to make this work I will be glad
to hear it.
Fixes bug #110369.
* lib/m4sugar/m4sh.m4
(_AS_IF_ELSE): When $1 is nonempty, invoke _AS_EMPTY_ELSE_PREPARE.
Emit $as_nop at beginning of else clause.
(_AS_BOURNE_COMPATIBLE): Initialize as_nop to ‘:’.
(_AS_EMPTY_ELSE_PREPARE): New macro which emits a definition of
as_fn_nop and resets as_nop to as_fn_nop.
(AS_PREPARE, _AS_PREPARE): Invoke _AS_EMPTY_ELSE_PREPARE.
(_AS_UNSET_PREPARE): Tweak white space.
* tests/m4sh.at (AS_IF and AS_CASE): Test AS_IF’s IF-FALSE argument
being empty after macro expansion.
* doc/autoconf.texi (AS_IF): Remove warning about use with
‘run-if-false’ argument empty after macro expansion.
Ross Burton [Wed, 11 Nov 2020 16:19:41 +0000 (11:19 -0500)]
Support CONFIG_SITE being a list of entries.
Instead of treating CONFIG_SITE as a single path, treat it as a
space-separated list of paths and load them in order.
Also remove the special-casing of entries starting with a dash, this is
redundant as they'll be caught by the wildcard case.
Finally add a test case to verify that multiple files are loaded
correctly.
* lib/autoconf/general.m4 (AC_SITE_LOAD): Treat CONFIG_SITE as a
space-separated list of scripts to be sourced. Simplify handling
of default config.site locations using this capability.
* tests/base.at (AC_CACHE_CHECK): Test loading of multiple site files.
* doc/autoconf.texi (Site Defaults): Update documentation of CONFIG_SITE.
In 2003, Joey Hess reported the following bug against Debian's
autoconf package (see http://bugs.debian.org/221483):
I noticed that if I ctrl-c autoconf, it can leave a partially
written, executable configure script. I was lucky enough to
get a configure script that exited with a shell parse error,
but if I had been unlucky, it might have exited 0 without
doing all the tests I expected it to do. That would have
sucked to ship to users.
There are many ways to update a file in a way that is not
prone to these problems, and I suggest that autoconf adopt
one of them.
Ben Pfaff wrote a patch to make autom4te replace the output file
atomically; Debian has carried it since 2006. He submitted it
to autoconf upstream in 2008 but it never went anywhere.
I (Zack) have dusted off the patch and made some minor improvements:
using File::Temp (with DIR set to the directory of the output file)
instead of a predictable temporary file name, and using
Autom4te::FileUtils::update_file instead of File::Copy::move.
I do not attempt to test the fix (the test would be inherently racey)
nor do I have autom4te delete the temp file if it crashes while the
file is being written (there is no way to do this with 100%
reliability and it strikes me as likely to cause more problems than it
solves).
Fixes our bug #110305.
* bin/autom4te.in (handle_output): When $output is to a regular or
nonexistent file, write to a temporary file in the same directory
and then rename it over $output after completion.
Zack Weinberg [Mon, 9 Nov 2020 20:15:23 +0000 (15:15 -0500)]
m4sh: Require shell to support $(...) command substitution.
As of the 2020-11-07 update, config.sub and config.guess
unconditionally use $(...) command substitution; see
<https://lists.gnu.org/archive/html/config-patches/2020-11/msg00011.html>.
Therefore, add this to the set of required shell features, searched
for by _AS_DETECT_BETTER_SHELL. On a system where /bin/sh doesn’t
support $(...), $CONFIG_SHELL will be set to one that does (and the
primary configure script will be re-executed using that shell).
AC_CANONICAL_* use $CONFIG_SHELL to execute config.guess/sub, so they
will keep working. This also means that configure scripts and
third-party macros that use $(...) will quietly start working
correctly on such ancient systems.
The test code is simple, but sufficient to weed out Solaris 10’s
/bin/sh, which doesn’t support $(...) but *does* support shell
functions.
I’m not going to touch any of the existing uses of `...` command
substitution in Autoconf proper for now, but it might make sense to
bulk upgrade them early in the 2.71 release cycle; if nothing else,
it would remove a major obstacle to running shellcheck over our
scripts.
* lib/m4sugar/m4sh.m4 (_AS_MODERN_CMDSUBST_WORKS): New macro.
(AS_INIT, AS_SHELL_SANITIZE): Call _AS_DETECT_REQUIRED for
_AS_MODERN_CMDSUBST_WORKS.
* NEWS: Mention the requirement for $(...).
Zack Weinberg [Mon, 9 Nov 2020 18:44:49 +0000 (13:44 -0500)]
Check in install-sh as synced from automake (#110368)
As pointed out in sr #110368, since install-sh is now being installed
as part of autoconf, we should make sure to ship the latest version
rather than the version shipped by the automake that was used to
bootstrap the autoconf release tarball.
The build-aux/fetch.pl script is already supposed to fetch the latest
version, but install-sh is listed in .gitignore so any updates are
discarded when starting from a clean tree. Correct this.
At the same time, since mdate-sh is *not* installed by autoconf nor is
it directly referenced in any code maintained in the autoconf
repository, remove it from the list of files to fetch and keep it in
.gitignore.
This change exposed a bug in fetch.pl where it would crash when
there was no old copy of a file being updated.
* .gitignore: Remove /build-aux/install-sh.
* build-aux/fetch.pl (%to_fetch): Remove build-aux/mdate-sh.
(slurp): Don’t die on ENOENT, return undef.
(replace_if_change): Handle $oldcontents being undef.
* build-aux/install-sh: Is now checked in.
Michał Górny [Fri, 16 Oct 2015 10:53:55 +0000 (12:53 +0200)]
autoreconf: Support AM_GNU_GETTEXT_REQUIRE_VERSION
As reported in https://github.com/gentoo/gentoo/pull/163, gettext 0.19.6
supports using AM_GNU_GETTEXT_REQUIRE_VERSION (specifying a *minimum*
required version of gettext) instead of AM_GNU_GETTEXT_VERSION
(which specifies a *fixed* required version of gettext).
Update autoreconf to support both.
* bin/autoreconf.in (autoreconf_current_directory): Check for
AM_GNU_GETTEXT_REQUIRE_VERSION as well as AM_GNU_GETTEXT_VERSION.
Update diagnostics about using AM_GNU_GETTEXT_VERSION but not
AM_GNU_GETTEXT, or vice versa, to match.
* doc/autoconf.texi (autoreconf Invocation): Update to match.
Zack Weinberg [Mon, 9 Nov 2020 18:08:13 +0000 (13:08 -0500)]
Fix more bugs in specific tests under AC_LANG(C++).
Found by exhaustive testing for differences between probe results
under AC_LANG(C) and AC_LANG(C++).
* lib/autoconf/c.m4 (AC_C_FLEXIBLE_ARRAY_MEMBER): Cast result of
malloc for C++ compatibility.
* lib/autoconf/programs.m4 (_AC_PROG_LEX_YYTEXT_DECL): Declare yywrap
as extern "C" when compiling as C++.
Zack Weinberg [Thu, 5 Nov 2020 15:24:08 +0000 (10:24 -0500)]
Make ‘forbidden tokens, basic’ test more robust.
While testing the previous patch I noticed that the ‘forbidden tokens,
basic’ test can fail if it runs too fast, because the autom4te cache
files aren’t considered newer than configure.ac.
* tests/tools.at (forbidden tokens, basic): Add delays to ensure
autom4te.cache files are newer than configure.ac.
Zack Weinberg [Thu, 5 Nov 2020 15:19:26 +0000 (10:19 -0500)]
Do not apply --program-transform-name to build-aux scripts.
autoreconf expects to find $(pkgdatadir)/build-aux/config.sub etc
under those names, not names modified by --program-transform-name.
Placing them in $(pkgdatadir) is sufficient to keep parallel
installations of autoconf separate: anyone doing that would need
to adjust @PACKAGE@ anyway.
* lib/local.mk: Use a _DATA rule, not a _SCRIPTS rule, to install
config.guess, config.sub, and install-sh.
(install-data-hook-make-aux-scripts-executable): New hook rule.
Zack Weinberg [Thu, 5 Nov 2020 13:59:46 +0000 (08:59 -0500)]
Define AC_REQUIRE_AUX_FILE with AC_DEFUN.
Some widely used Automake recipes involve putting AC_REQUIRE_AUX_FILE
at top level of a configure script, and it uses AC_REQUIRE now, so it
needs to be defined with AC_DEFUN.
* lib/autoconf/general.m4 (AC_REQUIRE_AUX_FILE): Define with AC_DEFUN.
* tests/torture.at (Missing auxiliary files (foreign)): New test.
Zack Weinberg [Mon, 2 Nov 2020 22:16:00 +0000 (17:16 -0500)]
autoreconf.in: improve compatibility with old perl
In very old perls (I noticed this with 5.8.4), File::Temp objects are
not automatically stringified in all contexts where we expect them to
be, causing autoreconf to crash.
* bin/autoreconf.in (install_aux_file): Explicitly extract the
temporary file’s name from $temp, and use that in all the places we
were using $temp.
Zack Weinberg [Mon, 2 Nov 2020 21:56:32 +0000 (16:56 -0500)]
Revert to 2.69-compatible behavior in AC_PROG_LEX (#110346)
Commit 29ede6b96feee29c0c477d1659081bbdb82cd8b3 caused AC_PROG_LEX to
stop looking for a library that provides yywrap. This broke several
packages in a Debian archive rebuild.
Revert all the way to the 2.69 behavior, which was to set LEXLIB to
-ll or -lfl if that library defines yywrap, but allow AC_PROG_LEX to
succeed if neither -ll nor -lfl exists on the system, even if a lex
program that doesn't define yywrap would need it.
(This behavior was a bug, but people have come to depend on it.
See https://savannah.gnu.org/support/index.php?110269 and the
thread starting from
https://lists.gnu.org/r/autoconf-patches/2020-07/msg00013.html
for gory details.)
To provide a path away from bug-compatibility, AC_PROG_LEX now takes
one argument, documented as a whitespace-separated list of options.
Two options are defined: ‘yywrap’ means to look for yywrap and behave
as if lex is unavailable if it isn’t found; ‘noyywrap’ means to not
look for yywrap at all. These are mutually exclusive.
Fixes bug #110346.
* lib/autoconf/programs.m4 (AC_PROG_LEX): Add an argument which
can be either ‘yywrap’, meaning to look for yywrap in -ll, or
‘noyywrap’, meaning to not look for yywrap at all. In the
absence of either option, issue an obsoletion warning and
revert to behavior bug-compatible with 2.69.
* tests/semantics.at: Add more tests of AC_PROG_LEX.
* tests/mktests.sh: Exclude AC_PROG_LEX from autogenerated tests.
* doc/autoconf.texi: Update documentation of AC_PROG_LEX.
* NEWS: Update notes on AC_PROG_LEX.
Some of the compiler options that AC_OPENMP tests, mean “enable
OpenMP” to one compiler, but “write output to a file named ‘mp’ or
‘penmp’” to other compilers. The author of AC_OPENMP believed that
this could only happen if compilation was *successful*, but didn’t
realize that one of the options means “write *preprocessed* output to
a file named ‘penmp’” to SunPRO C, and that this *would* succeed on
the test program. (AC_LINK_IFELSE fails anyway, because the
compilation didn’t create conftest$exeext.)
The option that actually means “enable OpenMP” to SunPRO C is earlier
in the list than the option that means “write preprocessed output to a
file named ‘penmp’”, so we might never have noticed this, but for a
second bug: if you have a bad combination of Solaris operating system
patches installed, it’s possible for this compiler to
successfully *compile* a program that uses OpenMP, but then fail
to *link* it because the OpenMP runtime library is out of sync with
the core C library. AC_OPENMP doesn’t distinguish this case from
“that option doesn’t mean ‘enable OpenMP’” so it goes on to other
entries in the list and hits the “write preprocessed output” one.
Implement four layers of defensive measures against this mess:
- Use an #error directive instead of a compile-time syntax error
to halt compilation when _OPENMP is not defined.
- For each option that might mean “enable OpenMP”, first do an
AC_COMPILE_IFELSE to find out whether it really means that, and
then an AC_LINK_IFELSE to find out whether it works. If the
compilation succeeds but the link fails, bail out of the loop and
declare OpenMP to be unsupported.
- If a file named ‘mp’ or ‘openmp’ exists in configure’s working
directory when AC_OPENMP begins, error out. This means it is safe
to delete any file named ‘mp’ or ‘openmp’ that exists at the *end*
of AC_OPENMP.
- If a file named ‘mp’ or ‘openmp’ exists in the top level of the
source tree with a configure.ac that uses AC_OPENMP, have autoconf
error out, too.
Fixes bug #110353. Problem reported by Dagobert Michelsen.
* lib/autoconf/c.m4 (_AC_LANG_OPENMP(C)): Change ‘choke me’ to
‘#error "OpenMP not supported"’.
(AC_OPENMP): AC_REQUIRE _AC_OPENMP_SAFE_WD. For each option, do
both a compile test and a link test; if the compile test succeeds
but the link fails, don’t go on to other candidate options.
Delete files named ‘mp’ and ‘penmp’ after the loop.
(_AC_OPENMP_SAFE_WD): New macro, subroutine of AC_OPENMP. If files
named ‘mp’ or ‘penmp’ exist, error out both at autoconf time and at
configure time.
* tests/torture.at (Files clobbered by AC_OPENMP): New test.
* doc/autoconf.texi: Document requirement not to have files
named ‘mp’ or ‘penmp’ next to a configure.ac that uses AC_OPENMP.
Zack Weinberg [Mon, 2 Nov 2020 16:00:38 +0000 (11:00 -0500)]
testsuite: Isolate aclocal from third-party macros (#110352).
Several tests in the testsuite run a system-provided aclocal, which
will look into its $prefix/share/aclocal for third-party macros.
If those macros are buggy, aclocal may bomb out even though the test
doesn’t use them, causing the test to fail spuriously.
In all tests that need to run aclocal, create an empty directory and
give aclocal the --system-acdir option pointing at that directory.
This masks out all these potentially buggy macros. (It does *not*
mask out AM_INIT_AUTOMAKE, which aclocal will find in a different
directory.)
In all tests that run autoreconf but *don’t* need to run aclocal,
create an empty aclocal.m4 and set ACLOCAL=true in the environment.
Fixes bug #110352. Problem reported by Dagobert Michelsen.
* tests/fortran.at
* tests/tools.at
* tests/torture.at:
Set ACLOCAL=true in the environment in all tests that run
autoreconf but don’t need to run aclocal.
Set ACLOCAL="aclocal --system-acdir <empty directory>" in all
tests that do need to run aclocal.
Zack Weinberg [Mon, 2 Nov 2020 01:04:19 +0000 (20:04 -0500)]
AC_LANG_CALL(C++): Use ‘int’ for return type of conftest::$2.
Commit 326c9a547423d25c621bc5c0ef76edbf6eda8c92 introduced a custom
AC_LANG_CALL for C++. Jani Välimaa reports in
https://lists.gnu.org/archive/html/bug-autoconf/2020-10/msg00054.html
that the new code does not handle AC_CHECK_LIB([foo], [main])
correctly. This is not the recommended way to use AC_CHECK_LIB, but
it’s what you get if you autoupdate from AC_HAVE_LIBRARY, and some
people may not have bothered replacing main with a more appropriate
symbol.
This patch changes the return type of the fake function declaration
for AC_CHECK_LIB’s second argument to be ‘int’, which is sufficient to
make g++ 10.2.0 happy again. We’re still on thin ice, unfortunately;
the code generated by AC_LANG_CALL *always* has undefined behavior, in
both C and C++, unless by chance the real prototype of the function
we’re probing for happens to match our fake declaration. The only
permanent cure is to stop faking declarations, and that’s going to be
a challenge.
* lib/autoconf/c.m4 (AC_LANG_CALL(C++)): Use ‘int’ for the return
type of the fake function declaration, to avoid problems when
the function whose declaration we’re faking is ‘main’.
Zack Weinberg [Mon, 2 Nov 2020 00:23:12 +0000 (19:23 -0500)]
Don’t search for X11 when cross compiling (#110345)
This is undesirable because X11 development headers and libraries
found by searching /usr are much more likely to belong to the build
operating system than the host operating system (being cross-compiled
for). A particularly problematic case, from the original bug report,
is “using a sysroot where the target is binary compatible with the
host. In this case AC_PATH_X will happily look at /usr and say that
yes, X is available, even if the sysroot doesn't have X.”
To cross-compile X client applications, the recommended procedure is
to put X11 headers and libraries for the host system in the cross
compiler’s default search path; alternatively, --x-includes and
--x-libraries can be used.
Fixes bug #110345. Problem reported by Ross Burton.
* lib/autoconf/libs.m4 (_AC_PATH_X): Before doing anything else,
see whether a test compilation with no special options (just -lX11)
will work. If it doesn’t, only invoke _AC_PATH_X_XMKMF and
_AC_PATH_X_DIRECT when not cross compiling.
Zack Weinberg [Sat, 31 Oct 2020 13:57:13 +0000 (09:57 -0400)]
Ignore stderr when testing parallel autotest (#110351).
Non-release versions of bash (notably 5.1.0(1)-rc1, which was uploaded
to Debian unstable) print internal debugging messages like
TRACE: pid 411364: bgp_delete: deleting 432074
to the test driver’s stderr while executing the parallel test driver.
This causes spurious failures in the test suite. Chet Ramsey assures
me these are not a symptom of a bug in either bash or the driver code
(see https://lists.gnu.org/archive/html/bug-autoconf/2020-10/msg00047.html)
so have the test suite ignore them.
This fixes Savannah bug #110351.
* tests/autotest.at: Ignore stderr whenever running a micro-suite in
parallel mode, to avoid spurious failures due to internal debugging
messages that may be printed by bash.
Zack Weinberg [Thu, 29 Oct 2020 13:21:52 +0000 (09:21 -0400)]
tests/m4sh.at: prevent an undesirable expansion of __oline__.
The descriptive comment for AT_DATA_LINENO mentions __oline__, and
this is expanded when generating the testsuite, which is confusing
to anyone reading the generated testuite. Defang it with @&t@.
* tests/m4sh.at (AT_DATA_LINENO): Prevent expansion of __oline__
in the descriptive comment.
Jannick [Wed, 28 Oct 2020 14:59:27 +0000 (10:59 -0400)]
Treat msys(2) the same as cygwin when looking at host_os.
In most cases, checks depending on the value of $host_os should
treat *-*-cygwin*, *-*-msys*, and *-*-mingw* all the same.
* lib/autoconf/fortran.m4 (_AC_FC_LIBRARY_LDFLAGS):
Discard -lkernel32 on msys* as well.
When not discarding -lkernel32, deduplicate it, like other -l options.
* lib/autoconf/functions.m4 (AC_FUNC_MALLOC, AC_FUNC_REALLOC):
msys* also guarantee to return nonnull for malloc(0)/realloc(0).
* tests/local.at (at_check_env): Also ignore MSYS as an environment
variable.
Zack Weinberg [Tue, 20 Oct 2020 17:36:58 +0000 (13:36 -0400)]
Improve handling of missing aux scripts (autoreconf)
Make ‘autoreconf --install’ add config.sub, config.guess, and
install-sh to the source tree when necessary. This is only relevant
for packages that don’t use Automake, because ‘automake --add-missing’
already adds these scripts to the source tree, but apparently there
are plenty of packages out there that don’t use Automake, didn’t need
config.{sub,guess} with autoconf 2.69, and do need them with 2.70.
Such packages will need to have their equivalent of ‘make dist’
manually updated to ship the new files, of course.
This patch also has ‘autoreconf’ issue an error if aux files are
missing and ‘--install’ *wasn’t* used, or if --install *was* used but
could not install all the missing files. This error is more likely to
be caught by maintainers than the configure-time error added in the
previous patch. It is not currently practical to make autoconf itself
issue this error message, because of how the autoconf wrapper script
is different from all the other wrapper scripts. Also, autoreconf
runs automake *after* autoconf, so we’d get spurious errors from
packages that do use automake.
* bin/autoreconf.in ($buildauxdir): New package global, initialized
to $pkgdatadir/build-aux, or to $ENV{autom4te_buildauxdir} if that’s set.
(find_missing_aux_files, can_install_aux_files, try_install_aux_files)
(install_aux_file, make_executable): New subs.
(autoreconf_current_directory): Trace AC_REQUIRE_AUX_FILE.
After running all tools that might install aux files, try to
install aux files ourself if --install was given.
After that, report on any that are still missing.
* lib/autom4te.in (Autoreconf-preselections): Add AC_REQUIRE_AUX_FILE.
Make list order consistent with list order in autoreconf.in.
* tests/wrapper.as: Set autom4te_buildauxdir to point to location of
config.guess, config.sub, and install-sh within the source tree.
* lib/local.mk: Install config.guess, config.sub, and install-sh
into $(pkgdatadir)/build-aux.
* doc/autoconf.texi: Document that autoreconf can now install
config.guess, config.sub, and install-sh itself without help from
automake, but packages not using automake will need to arrange for
tarball distribution of these files by hand.
* tests/torture.at (Missing auxiliary files): Test autoreconf as well.
Zack Weinberg [Tue, 20 Oct 2020 17:27:22 +0000 (13:27 -0400)]
Improve handling of missing aux scripts.
Another regression identified by the Debian archive rebuild was that
more macros require the presence of config.sub and config.guess now.
‘autoreconf --install’ doesn’t install these itself, it relies on
‘automake --add-missing’ to do that; so, packages that don’t use
Automake will fail at the configure stage after configure is
regenerated. To make matters worse, AC_CONFIG_AUX_DIRS assumes that
everyone who needs config.sub and config.guess also needs install-sh,
so in about half of the affected packages, the failure manifested as a
complaint about install-sh being missing -- technically true but
adding install-sh wouldn’t have resolved the problem by itself.
This patch overhauls the AC_CONFIG_AUX_DIR(S) mechanism so that a
configure script knows the complete set of aux scripts that were
AC_REQUIRE_AUX_FILE’d for it, checks for the existence of all of
them, and not any others. Thus, this configure script
will work fine in a directory that contains config.sub and
config.guess but not install-sh. Also, if it’s in a directory
that *doesn’t* contain config.sub and config.guess, it will print an
accurate error message
configure: error: cannot find install-sh, install.sh, or shtool in "." "./.." "./../.."
A side-effect: it doesn’t make sense for AC_CONFIG_SUBDIRS to demand
the presence of Cygnus configure in the aux dir, on the off-chance
that one of the subdirectories *might* be using it -- I have no idea
where someone would even get a copy of that nowadays -- so I dropped
that feature. I rather suspect nobody has needed it in over a decade.
I also documented the expanded need for config.sub and config.guess in
NEWS as well as the manual.
* NEWS: Document expanded need for config.sub and config.guess.
Document removed support for Cygnus configure in subdirectories.
* doc/autoconf.texi: Clarify exactly when install-sh, config.sub,
and/or config.guess are required. Document canonical online sources
for these scripts. Revise documentation of AC_CONFIG_AUX_DIR and
AC_REQUIRE_AUX_FILE. Minor improvements to documentation of
AC_CONFIG_SRCDIR. Remove mentions of Cygnus configure in
subdirectories.
* lib/autoconf/general.m4
(_AC_INIT_PARSE_ARGS): Remove mention of Cygnus configure;
clarify function of configure.gnu.
(AC_CONFIG_AUX_DIR): Support multiple invocations.
(AC_CONFIG_AUX_DIRS): Now an undocumented compatibility interface
rather than an internal subroutine; just runs AC_CONFIG_AUX_DIR on
each of its arguments.
(AC_CONFIG_AUX_DIR_DEFAULT): Now a backward compatibility stub that
requires _AC_INIT_AUX_DIR without adding anything to _AC_AUX_FILES.
(AC_REQUIRE_AUX_FILE): Now adds the named aux file to _AC_AUX_FILES
and requires _AC_INIT_AUX_DIR, as well as being a trace hook.
(_AC_INIT_AUX_DIR): New home of the loop searching for necessary aux
files (formerly in AC_CONFIG_AUX_DIRS). Looks for all the necessary
aux files, not just for install-sh.
(ac_config_guess, ac_config_sub, ac_configure): Issue deprecation
warnings if these undocumented shell variables are actually used.
(AC_CANONICAL_BUILD, AC_CANONICAL_HOST, AC_CANONICAL_TARGET):
No need to require AC_CONFIG_AUX_DIR_DEFAULT.
Can rely on $ac_aux_dir ending with a slash.
* lib/autoconf/programs.m4 (AC_PROG_INSTALL, AC_PROG_MKDIR_P):
No need to require AC_CONFIG_AUX_DIR_DEFAULT.
* lib/autoconf/status.m4 (_AC_CONFIG_SUBDIRS):
No need to require AC_CONFIG_AUX_DIR_DEFAULT.
Remove check for Cygnus configure; clarify function of configure.gnu.
* lib/autotest/general.m4: Remove mention of Cygnus configure.
* tests/torture.at (Missing auxiliary files): New test.
Zack Weinberg [Thu, 15 Oct 2020 00:22:41 +0000 (20:22 -0400)]
autoreconf: cope with empty AC_CONFIG_SUBDIRS (bug 110331)
Commit 41edf99f9515f3f83398428c39d79e11266a5a0d made all Perl warnings
fatal. This caused autoreconf to crash on packages that call
AC_CONFIG_SUBDIRS with no arguments. They probably shouldn’t do that,
but we shouldn’t crash if they do.
Problem reported by Ross Burton.
* bin/autoreconf.in (autoreconf_current_directory):
Convert undef to '' before attempting to split it.
* tests/torture.at (Empty AC_CONFIG_SUBDIRS): New test.
Paul Eggert [Mon, 12 Oct 2020 06:53:41 +0000 (23:53 -0700)]
doc: improve AS_CASE, AS_IF doc
See the thread containing:
https://lists.gnu.org/r/bug-gnulib/2020-10/msg00033.html
* doc/autoconf.texi: Distinguish between Solaris 10 and later.
(Balancing Parentheses): Mention the Posix syntax for ‘case’,
typically a better solution nowadays.
(AS_CASE, AS_IF): Mention AC_REQUIRE, portability, parens.
(Prerequisite Macros): Tighten up example and make it less dated.
Say that AS_CASE and AS_IF are not needed outside macros.
* NEWS: Don’t mention AS_FOR. It’s not documented, and for
good reason since it is so ... quirky.
Zack Weinberg [Sat, 10 Oct 2020 18:07:53 +0000 (14:07 -0400)]
_AS_PATH_WALK: Use AS_IF for IF-NOT-FOUND argument.
The construct _AS_PATH_WALK was using to conditionally execute its
IF-NOT-FOUND argument, was a little too fragile: relatively natural
variations in usage, such as putting the final `])` on a line by
itself, could cause shell syntax errors. Use AS_IF instead.
* lib/m4sugar/m4sh.m4: Use AS_IF to execute IF-NOT-FOUND conditionally.
Zack Weinberg [Fri, 9 Oct 2020 13:02:47 +0000 (09:02 -0400)]
Fix regressions when using the C++ compiler to perform tests.
The Debian project has done an archive rebuild using autoconf 2.69c,
which found several serious regressions from 2.69 where test programs
used to be accepted by a C++ compiler, but are now rejected. Part of
the problem is that newer C++ compilers are more likely to reject
“traditional” sloppy C, but part of it is that bug fixes since 2.69
did not consider the possibility of test macros being used with
AC_LANG([C++]) in effect.
I’m still working on test suite improvements that will catch these
regressions in the future, but I don’t see any reason to delay the
actual bugfixes. (I’ve gotten far enough on the test suite changes
that I know they _will_ catch the bugs.)
* NEWS: Document that AC_FUNC_STRERROR_R no longer tries to detect a
strerror_r that exists in the C library but isn’t declared by string.h.
* lib/autoconf/c.m4
(AC_LANG_CALL(C++)): New macro. Use a more robust technique for
avoiding a type conflict with any intrinsic prototype.
(AC_LANG_CALL(C)): Remove #ifdef __cplusplus, this macro is no longer
used to generate C++ code.
* lib/autoconf/functions.m4
(AC_FUNC_CLOSEDIR_VOID): Rely on <dirent.h> to declare closedir.
Simplify test program. Use AC_COMPILE_IFELSE, not AC_RUN_IFELSE.
(_AC_FUNC_MALLOC_IF, _AC_FUNC_REALLOC_IF): Use void *, not char *,
for variable holding a value returned by malloc/realloc respectively.
(AC_FUNC_STRERROR_R): Don’t AC_CHECK_FUNCS_ONCE strerror_r.
AC_DEFINE HAVE_STRERROR_R if and only if we are also going to define
HAVE_DECL_STRERROR_R. Remove AC_RUN_IFELSE fallback when strerror_r
is not declared.
* lib/autoconf/headers.m4 (AC_USG): Use "", not 0, for the first
argument to rindex.
Zack Weinberg [Wed, 7 Oct 2020 13:01:16 +0000 (09:01 -0400)]
Don’t issue obsoletion warnings for AC_DIAGNOSE.
AC_DIAGNOSE is used in several extremely popular add-on macros,
notably AM_INIT_AUTOMAKE, AM_GNU_GETTEXT, and AC_LIBTOOL_DLOPEN.
Until newer versions of these macros are available, -Wobsolete
warnings for AC_DIAGNOSE will be unhelpful noise.
Therefore, make it so AC_DIAGNOSE(...) will still be replaced with
m4_warn(...) by autoupdate, but autoconf runs will not complain about
AC_DIAGNOSE. The bulk of the patch is augmenting AU_DEFUN so that it
can define a “silent” autoupdate replacement, and documenting the new
feature.
* lib/autoconf/autoupdate.m4 (AU_DEFUN): Add a fourth argument, SILENT,
which must be either empty or the word ‘silent’. If it is ‘silent’,
the macro being defined will *not* issue a -Wobsolete warning when
expanded by autoconf.
Tweak quotation to prevent emacs’ parenthesis matching from getting
confused.
(AU_ALIAS): Add the SILENT argument here as well.
* lib/autoconf/general.m4 (AC_DIAGNOSE): Define as a silent AU_DEFUN.
Add commentary explaining why this was done and when it can be
changed back.
* doc/autoconf.texi (AU_DEFUN, AU_ALIAS): Revise; document new SILENT
argument.
The changes are now classified into “backward incompatibilities”,
“new features”, “obsolete features and new warnings”,
“notable bug fixes”, and “autotest enhancements”.
Also make the warning about argument-quotation bugs more prominent
and explicit. (See for instance Savannah bug 110319.)
mktmpdir: Ensure that $tmp is always an absolute pathname.
Several autotools programs use ‘do’ to evaluate Perl code
generated into a file in the temporary directory created by
Autom4te::General::mktmpdir. If the environment variable
TMPDIR is a relative path, mktmpdir will set $tmp to a
relative path and we’ll end up trying to ‘do’ a relative
path, which searches for the file in @INC. This doesn’t
work under perl 5.26 or later, because ‘.’ was removed
from @INC in that version (for security reasons).
Ensure that mktmpdir sets $tmp to an absolute pathname.
Also use File::Temp::tempdir to create the temporary
directory, instead of shelling out to ‘mktemp -d’;
this eliminates a subprocess and means we don’t have
to worry about cleaning up the directory on exit.
Problem found by Kent Fredric and reported as
<https://bugs.gentoo.org/625576>.
Supersedes Gentoo’s autoconf-2.69-perl-5.26-2.patch.
* lib/Autom4te/General.pm
(mktmpdir): Use File::Temp to create temporary directory.
Ensure that $tmp is an absolute path.
(END): No need to clean up $tmp.
* tests/tools.at (autotools and relative TMPDIR): New test.
Autoupdate AC_{DIAGNOSE,FATAL,OBSOLETE,WARNING} and _AC_COMPUTE_INT.
While working on the previous patches I noticed that all of these
macros are officially obsolete, but autoupdate doesn’t replace them.
_AC_COMPUTE_INT is easy to autoupdate. AC_{DIAGNOSE,FATAL,WARNING}
require a little special handling because their replacements are
m4sugar macros, and autoupdate normally expands m4sugar macros as it
goes. Fortunately, the same workaround as is used for AC_FOREACH can
be applied. AC_OBSOLETE also needs that workaround, and cannot be
fully replaced automatically.
The bulk of the patch is removing internal uses of AC_DIAGNOSE.
* lib/autoconf/general.m4 (_AC_COMPUTE_INT): Define using AU_DEFUN.
(AC_DIAGNOSE, AC_FATAL, AC_WARNING): Autoupdate to m4_warn,
m4_fatal, and m4_warn([syntax], [$1]) respectively, using the same
paired AU_DEFUN/AC_DEFUN trick that is used for AC_FOREACH.
(AC_OBSOLETE): Autoupdate to m4_warn([obsolete], [$1]) and advise
hand-conversion to AU_DEFUN.
* lib/autoconf/autoupdate.m4 (AU_DEFUN): Tweak quoting so m4_warn([$3])
is emitted into the edited configure.ac instead of being expanded at
autoupdate time.
* tests/tools.at (autoupdating AC_FOREACH): Adjust grep expressions.
(autoupdating AC_DIAGNOSE and AC_WARNING): New test.
(autoupdating AC_FATAL): New test.
(autoupdating AC_OBSOLETE): New test.
* tests/mktests.sh (ac_exclude_list, au_exclude_list):
Exclude AC_DIAGNOSE, AC_FATAL, AC_FOREACH, AC_OBSOLETE, and AC_WARNING
if not already excluded.
This makes the Texinfo documentation consistent with the previous
changes. --help output regarding warnings is already drawn directly
from ChannelDefs.pm and thus does not need to be updated.
* doc/autoconf.texi: Update all ‘invocation’ sections to describe
-W/--warnings consistently, and to refer to m4_warn for the list
of categories.
(m4_warn): Document the complete current list of categories.
(Reporting Messages): Delete section.
(AC_DIAGNOSE, AC_WARNING, AC_FATAL): Move to Obsolete Macros.
Use WARNINGS to pass down warnings options from autoreconf.
autoreconf runs a bunch of subsidiary tools, and is expected to pass
along various command-line settings, such as those controlling
warnings. It has historically done this via the command line.
However, not all of the tools recognize the same set of command-line
warnings options. There’s an existing check for whether aclocal and
automake understand ‘--warnings’ at all, but it currently assumes that
automake will accept the same set of warnings *categories* that
autoconf does. This hasn’t actually been true for many years
and is known to cause problems; see the discussion starting at
<https://lists.gnu.org/archive/html/autoconf/2020-09/msg00000.html>.
Previous patches in this series (and related patches applied to
automake) have restored agreement between the current development
trunks of the two sets of tools on the set of warnings categories, but
we still need to deal with the possibility of the *installed* tools
not being in agreement.
If we use the WARNINGS environment variable to pass down warnings
options, instead of the command line, then all the tools are already
coded to ignore unknown warning categories, and this ceases to be an
issue. And we no longer need the check for ‘--warnings’ support in
automake, either.
Also, autoreconf as well should suppress warnings from its first
invocation of autoconf, which is for tracing purposes only and may
emit spurious warnings because aclocal.m4 is not yet in place.
* bin/autoreconf.in
($aclocal_supports_warnings, $automake_supports_warnings): Delete.
(@warning): Make local to sub parse_args.
(parse_args): Do not add --warnings options to $autoconf,
$autoheader, $aclocal, or $automake. Instead, set $ENV{WARNINGS}
appropriately. No longer necessary to probe for --warnings support
from aclocal and automake.
(autoreconf_current_directory): Set $ENV{WARNINGS} temporarily to
“none” when running autoconf in trace mode. Fix typo in comment.
Close $traces immediately after we’re done with it.
* tests/torture.at (Specific warnings options for autoreconf):
New test.
Disable all warnings when running autoconf as a subprocess.
autoheader and autoscan both run autoconf in trace mode, and
autoheader makes a point of passing down the warnings options.
This means autoheader prints warnings that a regular invocation
of autoconf would also print, so in the common case where both
are being run by autoreconf, the warnings are duplicated.
autoscan doesn’t pass down warnings options but it _does_ leave
the WARNINGS environment variable alone, which means it may issue
completely spurious warnings because the configure script is still
under construction.
Change this so that both programs disable all warnings for the
subsidiary invocation of autoconf, by not passing any warnings
options themselves, and by setting the WARNINGS environment variable
to “none” for the subprocess. For this to work correctly, the
‘args: --warnings syntax’ line has to be removed from autom4te.cfg
(m4sugar section). Since syntax warnings are on by default anyway,
the sole effect of this is to allow WARNINGS=none to turn off syntax
warnings.
The test suite changes are all to remove expectations of duplicate
diagnostics from autoheader.
* bin/autoheader.in: Do not pass warnings options down to subsidiary
autoconf, and set WARNINGS=none in the environment for that process.
* bin/autoscan.in: Set WARNINGS=none in the environment for subsidiary
autoconf.
* lib/autom4te.in (M4sugar): Remove ‘--warnings syntax’.
* tests/semantics.at, tests/torture.at: No longer expect various
diagnostics from autoheader as well as autoconf.
New utility function Autom4te::ChannelDefs::merge_WARNINGS.
This function merges a list of warnings categories into the environment
variable WARNINGS, returning a new value to set it to. The intended use
is in code of the form
{
local $ENV{WARNINGS} = merge_WARNINGS ("this", "that");
# run a command here with WARNINGS=this,that,etc
}
This is not used yet, but will be in the next patch.
* lib/Autom4te/ChannelDefs.pm (merge_WARNINGS): New function.
ChannelDefs.pm *ought* to be kept in sync between automake and autoconf,
because it defines the set of valid -W options, and autoreconf assumes
that it can pass arbitrary -W options to all of the tools it invokes.
However, it isn’t covered by either project’s ‘make fetch’ and it hasn’t
actually *been* in sync for more than 17 years.
This patch manually brings over all of the changes made on the
automake side. Once the complementary patch is applied by the
automake team, both versions of the file will be the same, and then we
can add it to the list in fetch.pl and not have this problem any more
in the future.
There are some user-visible consequences to bringing this file back
into sync. The only one worth mentioning in NEWS is that the ‘obsolete’
category of warnings is now on by default. This had quite a bit of
fallout throughout the testsuite. There are also some new warning
categories that get mentioned in --help output, but we don’t actually
generate any warnings in those categories, so people using ‘-Wall’
won’t see any change. More diagnostics are automatically tagged with
‘warning:’ or ‘error:’, which also had some fallout in the testsuite.
Finally, ‘-Werror’ no longer causes complaints about unknown warning
categories to be treated as hard errors.
Internally, there are some small API changes: ‘parse_warnings’ is no
longer usable as a ‘getopt’ callback function, and we now have a stub
Autom4te/Config.pm to match the automake code’s expectations. (This
file *should* also be synced from automake by ‘make fetch’, but we
can’t quite do that yet because it’s a generated file and our build
system is not prepared to handle adding *two* directories to @INC when
running a not-yet-installed Perl script. I plan to fix that after 2.70.)
As a side-effect of adding a Config.pm, ‘prog_error’ now says to
report the bug to bug-autoconf, not bug-automake. If this is why we
mostly haven’t been using prog_error for internal errors, we can stop
avoiding it. (I did not change anything to use prog_error in this
patch.)
* lib/Autom4te/ChannelDefs.pm: Merge from automake.
* lib/Autom4te/Config.pm: New file.
* lib/local.mk (dist_perllib_DATA): Add Autom4te/Config.pm.
* bin/autoconf.as: Update list of warning categories to match
Autom4te::ChannelDefs::usage.
* bin/autoheader.in (@warnings): New global.
(parse_args): Don’t use parse_warnings as a getopt callback.
(main): Add warnings options from our command line to $autoconf.
No need to turn on 'obsolete' warnings explicitly.
No need to include "warning: " in warning messages.
* bin/autom4te.in (parse_args): Don’t use parse_warnings as a getopt callback.
(main): No need to include "warning: " in warning messages.
* bin/autoreconf.in (parse_args): parse_warnings now takes only one argument.
* bin/autoupdate.in: Set WARNINGS=none in environment for all child processes.
* tests/local.at
(AT_CHECK_M4): Handle `autom4te: error: /usr/bin/m4 ...` like
`autom4te: /usr/bin/m4 ...`.
(_AT_CHECK_AC_MACRO): Add AUTOCONF-FLAGS argument, passed to both
autoconf and autoheader.
(AT_CHECK_MACRO): Default AUTOCONF-FLAGS argument to empty.
Pass that argument to autoheader as well as autoconf.
(AT_CHECK_AU_MACRO): Expect a “macro ‘NAME’ is obsolete’ diagnostic
on the first run of autoconf. Pass -Wno-obsolete to autoconf on the
second run, and to autoheader on both runs.
* tests/base.at
* tests/c.at
* tests/compile.at
* tests/m4sh.at
* tests/m4sugar.at
* tests/semantics.at
* tests/tools.at
* tests/torture.at:
No need to pass -Wobsolete to autoconf.
Pass -Wno-obsolete to autoheader where needed to avoid handling
the same warning twice.
Update various expectations for diagnostics to match behavior
changes.
* tests/tools.at (autoupdating AU_ALIAS): Add an AC_CONFIG_HEADERS
line to the test configure.ac to eliminate an unrelated diagnostic.
Jonathan Wakely [Tue, 22 Sep 2020 19:45:10 +0000 (15:45 -0400)]
doc: Fix cross-reference for AC_TRY_LINK
The documentation for AC_TRY_LINK has a cross-reference to "Running
the Compiler". This should be "Running the Linker" instead. Also
make the link in AC_TRY_LINK_FUNC consistent.
Commit 9b5c0f17741836e99d0a801c6309389d391c03f9 introduced a bug where
autoconf --help would only print “Try 'autoconf --help' for more information.”
Correct this.
* bin/autoconf.as: Print $help, not $usage_err, for --help.
Consistently use AS_ECHO, not bare echo.