Based on a report by Michael Felt, via Paul Eggert on the
coreutils list.
* doc/autoconf.texi (Limitations of Builtins) <for>: Document
problem with 'for var in ;'.
Signed-off-by: Eric Blake <eblake@redhat.com>
* lib/autoconf/general.m4 (_AC_UNDECLARED_WARNING): New macro.
(_AC_CHECK_DECL_BODY): Call it once per language; treat warnings as
errors when its verdict indicates that.
* tests/semantics.at (AC_CHECK_DECLS): Add a macro call that relies on
the new semantics. Avoid -Wmissing-variable-declarations warnings.
* doc/autoconf.texi (Generic Declarations): Document the implications.
* NEWS: Mention this change.
Give a more concrete description of what the m4_pattern_forbid
thingy that pretends it is a macro accepts as an argument.
Copyright-paper-exempt: Yes
Signed-off-by: Eric Blake <eblake@redhat.com>
Based on an idea by Bernhard Reutner-Fischer.
We frequently used the idiom of 'test "${var+set}" = set' to
test if $var was set to a non-empty string, but this can portably
be trimmed to a more compact 'test ${var+y}' for a smaller
configure file. Testing that a variable is not set can be done
with '${var+false} :' (although the value of $? is not reliably
1 when the variable is set).
The code for AS_VAR_TEST_SET already used the form '${var+:} false',
but it is slightly longer, and does not guarantee $? of 1.
Tested on coreutils, where the resulting configure file is about
1k smaller.
* doc/autoconf.texi (Shell Substitutions): Prefer shorter sequence
for testing if a variable is set.
(Limitations of Builtins) <test (strings)>: Document it.
* configure.ac: Use it.
* lib/autoconf/c.m4 (_AC_PROG_CC_G, _AC_PROG_CXX_G)
(_AC_PROG_OBJC_G, _AC_PROG_OBJCXX_G): Likewise.
* lib/autoconf/fortran.m4 (_AC_PROG_FC_G): Likewise.
* lib/autoconf/general.m4 (_AC_ENABLE_IF_ACTION, AC_CACHE_SAVE):
Likewise.
* lib/autoconf/lang.m4 (_AC_COMPILER_EXEEXT_DEFAULT): Likewise.
* lib/autoconf/programs.m4 (AC_PROG_INSTALL, AC_PROG_MKDIR_P)
(_AC_PROG_LEX_YYTEXT_DECL): Likewise.
* lib/autoconf/status.m4 (_AC_OUTPUT_MAIN_LOOP): Likewise.
* lib/autotest/general.m4 (AT_INIT): Likewise.
* tests/base.at (AC_CACHE_CHECK): Likewise.
* tests/m4sh.at (LINENO): Likewise.
* lib/m4sugar/m4sh.m4 (_AS_BOURNE_COMPATIBLE)
(_AS_DETECT_BETTER_SHELL, _AS_SHELL_SANITIZE)
(_AS_PATH_SEPARATOR_PREPARE): Likewise.
(AS_VAR_TEST_SET): Use shorter sequence.
Signed-off-by: Eric Blake <eblake@redhat.com>
As a minor optimization, most macros in m4sugar.m4 try to avoid
output of 'dnl' in the expansion, to reduce the number of macros
that must be expanded at each call site.
* lib/m4sugar/m4sugar.m4 (m4_set_foreach): Don't expand dnl in all
callers.
Signed-off-by: Eric Blake <eblake@redhat.com>
Merging two case globs into one gives slightly smaller files and
less time spent in shell globbing on systems that lack GNU mkdir.
* lib/autoconf/programs.m4 (AC_PROG_MKDIR_P): Combine two GNU cases.
Signed-off-by: Eric Blake <eblake@redhat.com>
* tests/local.mk (check-local): Add a leading "+",
to void false-positive test failures when running
them in parallel. Before this change, running e.g.,
"make check TESTSUITEFLAGS=--jobs=15" would always
fail the two "make"-invoking tests: "C unit tests"
and "C unit tests (EXEEXT)".
(installcheck-local): Likewise for "installcheck".
This follows up on a comment by Glenn Morris in:
http://lists.gnu.org/archive/html/emacs-devel/2015-01/msg00011.html
* doc/autoconf.texi (Limitations of Usual Tools):
Remove circa-1990 advice about avoiding cp -f and ln -f.
Although that advice was reasonable for the early 1990s, the -f
option is portable for both cp and ln nowadays. These options
were standardized in POSIX 1003.2-1992, and pre-POSIX systems such
as SunOS 4 are no longer of practical concern.
The testsuite used slightly different logic in the code employed to
decide whether a test should be skipped due to a limitation of the
selected shell, and in the code running the test itself.
* tests/autotest.at (Syntax error): Adjust.
(parallel syntax error): Likewise.
Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
Based on a report by Bruce Dubbs.
* tests/foreign.at (Libtool): Be tolerant of 'quote' replacing the
older `quote'.
Signed-off-by: Eric Blake <eblake@redhat.com>
There has been a LOT of news about bash's Shell Shock bug lately.
Document some of the ramifications it has on portable scripting.
* doc/autoconf.texi (Limitations of Builtins) <export>: Add some
details about Shell Shock CVE-2014-6271.
Signed-off-by: Eric Blake <eblake@redhat.com>
* doc/autoconf.texi (C Compiler, Objective C Compiler)
(Objective C++ Compiler, Fortran Compiler): Be more careful about
distinguishing GNU C from GCC, and similarly for other languages.
Problem reported by Marko Lindqvist in:
http://lists.gnu.org/archive/html/autoconf/2014-09/msg00027.html
* lib/autoconf/lang.m4 (_AC_COMPILER_EXEEXT_CROSS):
When only --host is set, and no --build, but in the end, the resulting
computed $build and $host are different, set $cross_compiling = yes.
Indeed we can't rely only on a successful test program run, because false
positives occur on some platforms. In particular modern GNU/Linux
distributions set Wine to automatically handle Windows binaries.
Consequently $cross_compiling gets set to "no" even though we are in an
obvious cross-compilation case.
(tiny change)
* lib/autoconf/c.m4 (AC_C_VARARRAYS): Define __STDC_NO_VLA__ if
VLAs are not supported, as this is what C11 does. The old macro
HAVE_C_VARARRAYS is still defined if they are supported, but is
now obsolescent. Also, check for VLA bug in GCC 3.4.3.
* doc/autoconf.texi (C Compiler), NEWS: Document the above.
* doc/autoconf.texi: Specify @documentencoding UTF-8. Don't abuse
'`' to mean open quote, unless Texinfo already interprets it that
way. Be more careful about hyphen versus minus versus endash
versus emdash.
Dimitrios Apostolou reported getting a shell syntax error for
this construct in his configure.ac:
AM_CONDITIONAL([HAVE_LIBXML2],
[test "x$with_libxml2" != xno &&
test "x$ac_cv_lib_xml2_xmlFirstElementChild" = xyes]
)
He analyzed it to a root cause: his trailing newline, coupled
with an 'if $2; then' construct in the macro body, resulted in
configure containing:
if test ... xyes
; then
where the semicolon is a syntax error in shell; and proposed
a patch to automake to fix his use case.
While that macro is not under our control, it does highlight
the fact that the shell can use either ; or newline to
terminate a conditional prior to the next keyword in a compound
statement. If we use newline, we gain two benefits - the
configure file is slightly smaller (more lines, but fewer
bytes), and any user that doesn't realize that unquoted
trailing newlines in a macro argument are still significant
can still generate valid shell code when their argument is
used in a shell compound statement.
* lib/m4sugar/m4sh.m4 (AS_IF, _AS_IF, _AS_CLEAN_DIR): Prefer
newline over semicolon to end user-supplied conditionals.
* lib/autoconf/general.m4 (AC_CONFIG_AUX_DIRS): Likewise.
* lib/autoconf/libs.m4 (AC_SEARCH_LIBS): Likewise.
* lib/autoconf/programs.m4 (_AC_PATH_PROGS_FEATURE_CHECK):
Likewise.
* tests/m4sh.at (AS_IF and AS_CASE): Test it.
Signed-off-by: Eric Blake <eblake@redhat.com>
Changes:
configure: error: invalid feature name: debug
to
configure: error: invalid feature name: `debug '
to make it obvious if trailing space is the reason why a feature
name was rejected; similar to existing error messages elsewhere
about invalid shell variable names.
* lib/autoconf/general.m4 (_AC_INIT_PARSE_ENABLE2): Add quotes.
Reported by Noel Grandin.
Signed-off-by: Eric Blake <eblake@redhat.com>
This patch changes "main ()" to "main (void)" for C/C++.
See: http://lists.gnu.org/archive/html/bug-autoconf/2014-01/msg00005.html
On my machine, before this patch, 3 tests were failing:
38: tools.at:1329 autom4te cache locking
218: autotest.at:1893 C unit tests
ac_config_testdir at_tested autotest
219: autotest.at:1948 C unit tests (EXEEXT)
ac_config_testdir at_tested autotest
With this patch, 2 tests were failing:
218: autotest.at:1893 C unit tests
ac_config_testdir at_tested autotest
219: autotest.at:1948 C unit tests (EXEEXT)
ac_config_testdir at_tested autotest
(I suspect that 38 is unrelated.)
Signed-off-by: Vincent Lefevre <vincent@vinc17.net>
Copyright-paperwork-exempt: Yes
The autoconf manual doesn't mention any examples of actually
using m4_pattern_forbid. Yet this is the perfect macro for
avoiding the all-too-common failure mode of configure dying with:
checking if libxml2 is present... ./configure: line 11586: syntax
error
near unexpected token `LIBXML2,'
./configure: line 11586: `PKG_CHECK_MODULES(LIBXML2, libxml-2.0>=
2.6.19,'
for developers that forgot to install pkg-config. While we don't
necessarily advertise the use of PKG_CHECK_MODULES, it is a
common enough situation that the manual should make it easier to
help developers learn about missing third-party macros.
Based on a mailing list report by Daniel Pocock:
http://lists.gnu.org/archive/html/autoconf/2014-01/msg00030.html
* doc/autoconf.texi (Forbidden Patterns): Add examples.
Signed-off-by: Eric Blake <eblake@redhat.com>
Test 236 "configure directories" failed for me on 64-bit Fedora 20;
it boiled down to the system's config.site causing libdir to
default to /usr/lib64 instead of the autoconf default of /usr/lib.
* tests/base.at (configure directories): Neutralize any preinstalled
config.site from the system.
Signed-off-by: Eric Blake <eblake@redhat.com>
Fix syntax check warnings that are unrelated to the new copyright
year.
* lib/local.mk (lib/autoscan/autoscan.list): Reduce indent, to
avoid mix of tab and 8 spaces.
* bin/local.mk (bin/autoconf.in): Likewise.
* lib/autoconf/c.m4 (_AC_CXX_CXX98_TEST_BODY): Use consistent case
in message.
Signed-off-by: Eric Blake <eblake@redhat.com>
Done via 'make update-copyright', since all files are effectively
modified and distributed this year via public version control.
* all files: Update copyright year.
* lib/autoconf/functions.m4 (AC_FUNC_CHOWN): No need to check for unistd.h.
(_AC_LIBOBJ_FNMATCH): Use AC_CHECK_DECLS_ONCE and AC_CHECK_FUNCS_ONCE.
(_AC_LIBOBJ_GETLOADAVG): Use AC_CHECK_FUNCS_ONCE for setlocale.
(AC_FUNC_MMAP): Use AC_CHECK_FUNCS_ONCE for getpagesize.
(AC_FUNC_SELECT_ARGTYPES): Use AC_CHECK_HEADERS_ONCE for sys/select.h and
sys/socket.h.
(AC_FUNC_STRERROR_R): Use AC_CHECK_DECLS_ONCE + AC_CHECK_FUNCS_ONCE for
strerror_r.
(AC_FUNC_UTIME_NULL): Use AC_CHECK_HEADERS_ONCE for utime.h.
(AC_FUNC_FORK): Use AC_CHECK_HEADERS_ONCE and AC_CHECK_FUNCS_ONCE.
(AC_FUNC_VPRINTF): Use AC_CHECK_FUNCS_ONCE for vprintf (but not _doprnt).
* lib/autoconf/headers.m4 (AC_HEADER_TIME, AC_MEMORY_H): Use
AC_CHECK_HEADERS_ONCE.
* lib/autoconf/headers.m4 (AC_CHECK_HEADERS_ONCE): Divide into a public
macro that AC_REQUIREs _AC_INCLUDES_DEFAULT_REQUIREMENTS, and ...
(_AC_CHECK_HEADERS_ONCE): ... a private macro, that doesn't.
(_AC_HEADERS_EXPANSION): Use $ac_includes_default, not
AC_INCLUDES_DEFAULT.
(_AC_INCLUDES_DEFAULT_REQUIREMENTS): Use AC_CHECK_HEADERS_ONCE.
* lib/autoconf/headers.m4 (_AC_INCLUDES_DEFAULT_REQUIREMENTS):
Include stddef.h, stdlib.h, and string.h unconditionally.
Don't include memory.h at all.
Don't use AC_HEADER_STDC.
Don't check for stddef.h, stdlib.h, string.h, or memory.h.
For compatibility, unconditionally define STDC_HEADERS,
HAVE_STDLIB_H, and HAVE_STRING_H.
(AN_HEADER list): Remove C89 headers, and memory.h from list.
(AC_HEADER_STDC, AC_UNISTD_H): AU_DEFUN to trigger
_AC_INCLUDES_DEFAULT_REQUIREMENTS if it hasn't already happened,
and do nothing else.
(AC_HEADER_TIME): AU_DEFUN, and define TIME_WITH_SYS_TIME unconditionally
as long as sys/time.h is present.
(AC_USG, AC_MEMORY_H): Assume existence of string.h.
* lib/autoconf/functions.m4 (_AC_FUNC_MALLOC_IF, _AC_FUNC_REALLOC_IF):
Don't use AC_HEADER_STDC. Assume stdlib.h exists.
(AC_FUNC_MKTIME): Don't use AC_HEADER_TIME. Assume time.h exists.
(AC_FUNC_ALLOCA): Assume stdlib.h exists.
(_AC_LIBOBJ_FNMATCH): Assume wchar.h and wctype.h exist.
(_AC_LIBOBJ_GETLOADAVG): Assume locale.h exists.
(AC_FUNC_MMAP): Assume stdlib.h exists.
* tests/tools.at: Use AC_WORDS_BIGENDIAN instead of AC_STDC_HEADERS in
autoupdate test.
* NEWS, doc/autoconf.texi: Document changes. Remove obsolete advice.
* lib/autoconf/headers.m4 (AC_CHECK_HEADER): Use _AC_CHECK_HEADER_COMPILE
by default. Continue to use _AC_CHECK_HEADER_PREPROC if fourth arg is '-'.
(_AC_CHECK_HEADER_PREPROC): Issue a deprecation warning.
(_AC_CHECK_HEADER_MONGREL, _AC_CHECK_HEADER_MONGREL_BODY): Remove.
* tests/c.at, tests/semantics.at: Update uses of AC_CHECK_HEADER(S).
* doc/autoconf.texi, NEWS: Document change.
