make flags analysis: take advantage of GNU make features
* lib/am/header-vars.mk: Here. In particular ...
(am__make_keepgoing): ... rename this ...
(am.make.keep-going): ... like this, and reimplement using ...
(am.make.is-running-with-option): ... this new macro, cannibalized
from the old version of the 'am.make.dry-run' macro.
(am.make.dry-run): Reimplement using such new macro.
* lib/am/subdirs.mk: Adjust.
* t/make-keepgoing.tap: Likewise. While at, simplify by assuming
that $MAKE is GNU make, and enhance to test more setups (in particular,
this makes this test more in sync with the test 't/make-dryrun.tap').
* t/make-dryrun.tap: While at it, remove an extra empty line.
* master:
docs: fix warnings given by Texinfo 5.x
fixlet: remove leftover comment fragment
master branch: we are going to become Automake 2.0
maint branch: we are going to become Automake 1.14
maint: version bump after beta release 1.13.1d
release: beta release 1.13.1d (will become 1.13.2)
NEWS: document more robust handling/recognition of make options
tests: typofixes in comments in t/preproc-c-compile.sh
tests: remove bashism from a test
maint: targets and recipes to simplify testing on real-world packages
build: preparatory refactoring
build: tiny reduction in code duplication
make flags analysis: handle more options with args
make flags analysis: use simpler variable names
make flags analysis: whitespace changes
make flags analysis: embed in a subshell
make flags analysis: be more robust
make flags analysis: cater to GNU make 3.83 (still unreleased as of now)
tests: expose weaknesses in make flags analysis
tests: improve debugging output in checks on make flags analysis
make flags analysis: refactor, to reduce code duplication
tests: avoid one tricky use of "make -e"
cosmetics: remove few trailing whitespace occurrences
typofix: in NEWS (extra whitespace)
compat: substitute '@mkdir_p@' as '$(MKDIR_P)' unconditionally
tests: avoid a spurious error with Solaris make
subdirs: don't return false positives for the '-k' option's presence
header-vars: recognize more make flags ('-k' in particular)
header-vars: simplify how make flags are determined
tests: remove dead code from t/make-dryrun.tap
header-vars: new variable $(am__running_with_option)
tests: expose bug#12554 (false positives for presence of '-k' make option)
doc/automake.texi:3885: warning: node next `Public Macros' in menu \
`Private Macros' and in sectioning `Obsolete Macros' differ
doc/automake.texi:4050: warning: node `Private Macros' is next for \
`Obsolete Macros' in sectioning but not in menu
doc/automake.texi:4050: warning: node prev `Obsolete Macros' in menu \
`Private Macros' and in sectioning `Public Macros' differ
doc/automake.texi:4090: warning: node `Obsolete Macros' is next for \
`Private Macros' in menu but not in sectioning
doc/automake.texi:4090: warning: node prev `Private Macros' in menu \
`Public Macros' and in sectioning `Obsolete Macros' differ
* maint:
maint branch: we are going to become Automake 1.14
maint: version bump after beta release 1.13.1d
release: beta release 1.13.1d (will become 1.13.2)
NEWS: document more robust handling/recognition of make options
tests: typofixes in comments in t/preproc-c-compile.sh
tests: remove bashism from a test
* branch-1.13.2:
maint: version bump after beta release 1.13.1d
release: beta release 1.13.1d (will become 1.13.2)
NEWS: document more robust handling/recognition of make options
* maint:
maint: targets and recipes to simplify testing on real-world packages
build: preparatory refactoring
build: tiny reduction in code duplication
make flags analysis: handle more options with args
make flags analysis: use simpler variable names
make flags analysis: whitespace changes
make flags analysis: embed in a subshell
make flags analysis: be more robust
make flags analysis: cater to GNU make 3.83 (still unreleased as of now)
tests: expose weaknesses in make flags analysis
tests: improve debugging output in checks on make flags analysis
make flags analysis: refactor, to reduce code duplication
tests: avoid one tricky use of "make -e"
cosmetics: remove few trailing whitespace occurrences
typofix: in NEWS (extra whitespace)
tests: avoid a spurious error with Solaris make
subdirs: don't return false positives for the '-k' option's presence
header-vars: recognize more make flags ('-k' in particular)
header-vars: simplify how make flags are determined
tests: remove dead code from t/make-dryrun.tap
header-vars: new variable $(am__running_with_option)
tests: expose bug#12554 (false positives for presence of '-k' make option)
* branch-1.13.2:
maint: targets and recipes to simplify testing on real-world packages
build: preparatory refactoring
build: tiny reduction in code duplication
make flags analysis: handle more options with args
make flags analysis: use simpler variable names
make flags analysis: whitespace changes
make flags analysis: embed in a subshell
make flags analysis: be more robust
make flags analysis: cater to GNU make 3.83 (still unreleased as of now)
tests: expose weaknesses in make flags analysis
tests: improve debugging output in checks on make flags analysis
make flags analysis: refactor, to reduce code duplication
tests: avoid one tricky use of "make -e"
tests: avoid a spurious error with Solaris make
subdirs: don't return false positives for the '-k' option's presence
header-vars: recognize more make flags ('-k' in particular)
header-vars: simplify how make flags are determined
tests: remove dead code from t/make-dryrun.tap
header-vars: new variable $(am__running_with_option)
tests: expose bug#12554 (false positives for presence of '-k' make option)
Merge 'better-makeflags-recognition' and 'testing-work' into branch-1.13.2
* better-makeflags-recognition:
make flags analysis: handle more options with args
make flags analysis: use simpler variable names
make flags analysis: whitespace changes
make flags analysis: embed in a subshell
make flags analysis: be more robust
make flags analysis: cater to GNU make 3.83 (still unreleased as of now)
tests: expose weaknesses in make flags analysis
tests: improve debugging output in checks on make flags analysis
make flags analysis: refactor, to reduce code duplication
* testing-work:
maint: targets and recipes to simplify testing on real-world packages
build: preparatory refactoring
build: tiny reduction in code duplication
maint: targets and recipes to simplify testing on real-world packages
We introduce a new section in the maintainer-specific makefile that
contains recipes to test the build system of some well-known GNU
packages with the current development version of Automake. Not the
cleanest way to do so, but good enough for the moment. We'll revisit
the matter after the 1.13.2 release (which we now hope will happen
soon).
* maint.mk (git-sv-host): New.
(SV_GIT_CF, SV_GIT_AC, SV_GIT_GL): Use it to reduce code duplication.
(ALL_PACKAGES, FEW_PACKAGES): New, lists of GNU packages to try out.
(ttp-check, ttp-check-all): New targets, do the checking with said
packages.
(ttp): New, alias for 'ttp-check'.
(ttp-all): New, alias for 'ttp-check-all'.
The code was only duplicated two times, but we are soon going to
need a third occurrence, and that would be one to much.
* Makefile.am (extend_path): New.
(update_mans): Use it instead of copying & pasting its contents.
($(srcdir)/doc/amhello-1.0.tar.gz): Likewise, and minor related
adjustments.
* lib/am/header-vars.am (am__make_running_with_option): Here. Now
that we expect to be run in a subshell, we don't have to worry about
being namespace-safe. And '$foo' is much more pleasant to read than
'$am__foo' -- and pleasant code tends to be more correct.
(am__make_dryrun, am__make_keepgoing): Adjust.
make flags analysis: cater to GNU make 3.83 (still unreleased as of now)
The current development version of GNU make (that is planned to become
GNU make 3.83, sooner or later) has changed the format its $(MFLAGS)
variable slightly, removing the space between an option and its argument:
# With GNU make 3.82, compiled from official tarball:
$ make -f- <<<'all:; @echo "$$MFLAGS"' -I none
-I none
# With development version of GNU make (Git commit b5ea49b):
$ make -f- <<<'all:; @echo "$$MFLAGS"' -I none
-Inone
This was done on purpose, in order to support more easily the new
option '-O', which takes an optional argument; see:
Which was causing a spurious failure on FreeBSD. Not particularly
surprising, given how brittle "make -e" is in general ...
* t/cxx-lt-demo.sh: Instead of forcing $(CC) to be 'false' by
exporting "CC=false" in the environment and then passing the '-e'
option to make, do so by passing "CC=false" on the make command
line, both directly and using AM_MAKEFLAGS.
* fix-pr12554:
tests: avoid a spurious error with Solaris make
subdirs: don't return false positives for the '-k' option's presence
header-vars: recognize more make flags ('-k' in particular)
header-vars: simplify how make flags are determined
tests: remove dead code from t/make-dryrun.tap
header-vars: new variable $(am__running_with_option)
tests: expose bug#12554 (false positives for presence of '-k' make option)
compat: substitute '@mkdir_p@' as '$(MKDIR_P)' unconditionally
We had started to do so only when the obsolete AM_PROG_MKDIR_P variable
was used, but that has recently turned out not to be not good enough,
because Gettext 0.18.2 (the latest one at the moment of writing) is using
the modern macro AC_PROG_MKDIR_P in its '*.m4' files, but at the same time
is still using the obsolete make variable '$(mkdir_p)' in its Makefile
fragments. This has been causing failures in real-world packages
bootstrapped with latest Gettext (0.18.2) and with bleeding-edge automake.
And the worst things is that those failures have been basically silent
and unnoticeable up until the final "make install" --- that is, after
the affected package had been bootstrapped, configured and built. Yikes!
This issue has been reported to the Gettext developers:
But even if they will quickly fix it, Gettext 0.18.2 will remain
affected.
The fix we can implement in Automake is small and unobtrusive enough,
definitely worth having in order to save the users and developers from
having to deal with this hard-to-spot issue.
* m4/init.m4 (AM_INIT_AUTOMAKE): AC_SUBST '@mkdir_p@' to '$(MKDIR_P)'.
* t/am-prog-mkdir-p.sh: Enhance.
tests: adjust for warnings that have been moved to GNU make runtime
Some of those warnings are given at automake runtime in mainline
Automake, and some tests were relying on that behaviour, thus causing
spurious testsuite failures.
* master:
sync: update files from upstream with "make fetch"
maintcheck: remove outdated whitelisting
tar: format 'ustar' cannot support UID/GID longer than 21 bits
docs: issues with configure substitutions in TESTS
tests: avoid possible autotools caching issues (automake bug#13832)
tests: rename some with more descriptive names
docs: add myself and Ralf Wildenhues as authors
authors: add myself
dry-run: don't get confused by '-I' option
tests: avoid a spurious failure with the Korn Shell
dry-run: with GNU make, prefer $(MFLAGS) over $(MAKEFLAGS)
header vars: can determine whether we are running under GNU make
NEWS: improve wording for automake bug#13514 fix
NEWS: document fix for automake bug#13514
+ Extra non-trivial changes:
* lib/am/header-vars.am: Ignore all upstream changes, we shouldn't
need them.
* t/make-is-gnu.sh: Remove; our generated makefiles have no need to
test whether they are running under GNU make --- of course they are!
* maint:
sync: update files from upstream with "make fetch"
maintcheck: remove outdated whitelisting
tar: format 'ustar' cannot support UID/GID longer than 21 bits
docs: issues with configure substitutions in TESTS
tests: avoid possible autotools caching issues (automake bug#13832)
tests: rename some with more descriptive names
docs: add myself and Ralf Wildenhues as authors
authors: add myself
dry-run: don't get confused by '-I' option
tests: avoid a spurious failure with the Korn Shell
dry-run: with GNU make, prefer $(MFLAGS) over $(MAKEFLAGS)
header vars: can determine whether we are running under GNU make
NEWS: improve wording for automake bug#13514 fix
NEWS: document fix for automake bug#13514
* branch-1.13.2:
sync: update files from upstream with "make fetch"
maintcheck: remove outdated whitelisting
tar: format 'ustar' cannot support UID/GID longer than 21 bits
subdirs: don't return false positives for the '-k' option's presence
This change fixes automake bug#12554.
The old implementation of the code descending into $(SUBDIRS)
entries used the following snippet to decide whether make is running
with the '-k' a.k.a. '--keep-going' option, and thus whether a failure
in a subdirectory should prevent the descent in the following ones:
fail= failcom='exit 1'; \
for f in x $$MAKEFLAGS; do \
case $$f in \
*=* | --[!k]*);; \
*k*) failcom='fail=yes';; \
esac; \
done
It's clear that the second pattern in the 'case' construct could possibly
match false positives, for examples in these two cases:
make check TESTS="x.test k.test"
make -I /usr/local/kool-fragments
which are somewhat unusual, but not invalid. So we need a more resilient
implementation, as we did for the detection of the '-n' flag.
This implementation is now provided by the new private macro
'$(am__make_keepgoing)' (introduced in recent commits); so we can
just us that to fix the bug.
* lib/am/subdirs.am ($(am__recursive_targets)): Use '$(am__make_keepgoing)'
instead of ad-hoc and more brittle checks.
* t/list-of-tests.mk (XFAIL_TESTS): Remove the now-passing test case
't/subdir-keep-going-pr12554.sh'.
Reported-by: Michael Daniels <mdaniels@rim.com> Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
header-vars: recognize more make flags ('-k' in particular)
* lib/am/header-vars.am (am__running_with_option): Here.
Few improvements to comments, while at it.
(am__make_keepgoing): New, tell whther make is being runt with
the '-k' option.
* t/make-keepgoing.tap: New test.
* t/list-of-tests.mk: Add it.
* t/make-dryrun.tap: Minor edits to keep it more in sync with
the new test.
* syntax-checks.mk (sc_tests_overriding_macros_on_cmdline): Here.
The test 'make-dryrun.sh' has been since long rewritten as the TAP
test 'make-dryrun.tap', and no longer spuriously triggers this
maintainer check.
header-vars: simplify how make flags are determined
Actually, son far only the '-n' option ("dry mode") was detected,
but this change will allow us to soon detect more options.
* lib/am/header-vars.am (am__running_with_option): Even when $MAKEFLAGS
appears to contain definition of variables with embedded whitespace,
use simple textual pre-processing over $MAKEFLAGS rather than tricky
recursive invocations of make to determine whether the '-n' option was
given. This is enough to correctly handle all the tricky usages covered
in the testsuite.
* t/nodep.sh: Adjust to avoid a spurious failure.
header-vars: new variable $(am__running_with_option)
This is a preparatory refactoring, needed by later patches.
No semantic change is intended.
* lib/am/header-vars.am (am__running_with_option): New, contains
shell code that determines whether the current make instance is
running with a given one-letter option (e.g., -k, -n) that takes
no argument. Actually, the only supported option at the moment
is '-n' (support for '-k' will be added soon).
(am__make_dryrun): Rewrite as a thin wrapper around
'$(am__make_running_with_option)'.
tests: expose bug#12554 (false positives for presence of '-k' make option)
The current implementation of the code descending into $(SUBDIRS)
entries uses the following snippet to decide whether make is running
with the '-k' a.k.a. '--keep-going' option, and thus whether a failure
in a subdirectory should prevent the descent in the following ones:
fail= failcom='exit 1'; \
for f in x $$MAKEFLAGS; do \
case $$f in \
*=* | --[!k]*);; \
*k*) failcom='fail=yes';; \
esac; \
done
It's clear that the second pattern in the 'case' construct can possibly
match false positives, for examples in these two cases:
make check TESTS="x.test k.test"
make -I /usr/local/kool-fragments
which are somewhat unusual, but not invalid. So we need a more resilient
implementation, as we did for the detection of the '-n' flag.
But alas, such an implementation seems quite tricky to obtain in portable
make. So for the moment we content ourselves with exposing the bug, with
the hope of being able to fix soon enough.
* t/subdir-keep-going-pr12554.sh: New test.
* t/list-of-tests.mk (handwritten_TESTS, XFAIL_TESTS): Add it.
* THANKS: Update
Reported-by: Michael Daniels <mdaniels@rim.com> Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
tar: format 'ustar' cannot support UID/GID longer than 21 bits
See automake bug#8343 and bug#13588.
POSIX 1988 'ustar' format is defined with *fixed-size* fields. There
is notably a 21 bits limit (2097151) for the UID and the GID.
Tom Rini tom_rini@mentor.com says (in bug#8343):
When the user has a UID or GID that is larger than the ustar format
supports, pax does not error out gracefully in some cases (FC13).
Marc Herbert <marc.herbert@intel.com> adds (in bug#8343):
When "configure" is run by a user with an UID bigger than 21 bits,
BSD pax 3.4 aborts when trying to create the 'conftest.tar' test
archive and leaves an empty or corrupted conftest.tar file behind.
In the next step, pax tries to extract this incomplete or corrupted
archive and this *** hangs the whole ./configure script ***.
Note: GNU cpio 2.9 pretends to pass the test but it is a LIE: it
silently truncates any big UID to its lower 21 bits. I don't know
what can be the consequences of this lie.
I think there is currently a design issue in automake/m4/tar.m4
considering that a ustar archive should should *never* succeed when
./configure is run from a big user ID.
Months later, Petr Hracek <phracek@redhat.com> reports a similar issue
(in bug#13588) for Fedora 17:
I am trying to solve problem in case a user is created with big
UID and during configuration pax hangs with message
ATTENTION! pax archive volume change required.
Ready for archive volume: 1
Input archive name or "." to quit pax.
Archive name >
Time to fix this issue, on the line of a preliminary patch provided by
Petr Hracek in bug#13588. The final patch ended up being remarkably
different from that original proposition, though.
* m4/tar.m4 (_AM_PROG_TAR): If the UID or GID of the current user is
too high (> 2097151), the 'ustar' format cannot work. Adjust checks
accordingly. Some related code reordering and clean-up.
* t/tar-ustar-id-too-high.sh: New test.
* t/list-of-tests.mk: Add it.
* t/tar.sh: While at it, tweak and enhance a little.
* t/tar2.sh: Likewise.
* t/tar3.sh: Likewise.
* t/tar-override.sh: Likewise.
* NEWS: Update.
* THANKS: Likewise.
Helped-by: Pavel Raiskup <praiskup@redhat.com> Helped-by: Petr Hracek <phracek@redhat.com> Helped-by: Marc Herbert <marc.herbert@intel.com> Helped-by: Tom Rini <tom_rini@mentor.com> Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
* branch-1.13.2:
docs: issues with configure substitutions in TESTS
tests: avoid possible autotools caching issues (automake bug#13832)
docs: add myself and Ralf Wildenhues as authors
authors: add myself
dry-run: don't get confused by '-I' option
tests: avoid a spurious failure with the Korn Shell
dry-run: with GNU make, prefer $(MFLAGS) over $(MAKEFLAGS)
header vars: can determine whether we are running under GNU make
NEWS: improve wording for automake bug#13514 fix
NEWS: document fix for automake bug#13514
* fix-part-pr13832:
tests: avoid possible autotools caching issues (automake bug#13832)
* fix-pr13760:
dry-run: don't get confused by '-I' option
dry-run: with GNU make, prefer $(MFLAGS) over $(MAKEFLAGS)
header vars: can determine whether we are running under GNU make
* fix-doc-pr14019:
docs: issues with configure substitutions in TESTS
* news-wording-improve:
NEWS: improve wording for automake bug#13514 fix
docs: issues with configure substitutions in TESTS
Motivated by automake bug#14019.
* doc/automake.texi: Currently, when the parallel test harness is in use,
configure substitutions in TESTS definitions can only work if they expand
to tests that ends with a suffix listed in TEST_EXTENSIONS. Document this
limitation.
Fixes automake bug#13760 for non-GNU make implementations that still
support the option '-I'. So far, the only such make implementation
are FreeBSD (8.x) make and NetBSD (5.x) make.
* lib/am/header-vars.am (am__make_dryrun): If a non-GNU make is being
used, try to handle the '-I' option in $MAKEFLAGS correctly. For GNU
make, that is already done by the proper use of the $MFLAGS variable.
dry-run: with GNU make, prefer $(MFLAGS) over $(MAKEFLAGS)
Fixes automake bug#13760 for GNU make.
* lib/am/header-vars.am (am__make_dryrun): If GNU make is being used, rely
on the contents of the $(MFLAGS) variable rather than of the $(MAKEFLAGS)
to decide whther make is being executed in "dry run" mode. Not only this
makes the code possibly faster and less brittle, but also fixes automake
bug#13760 (at least when GNU make is in use).
* t/make-dryrun.tap: Adjust: some tests that were xfailing now pass.
header vars: can determine whether we are running under GNU make
This is mostly a preparatory patch in view of future changes.
* lib/am/header-vars.am (am__is_gnu_make): New, contains shell code that
determines whether we are running under GNU make.
* t/make-is-gnu.sh: New test.
* t/list-of-tests.mk: Add it.
* master:
INSTALL: regen
sync: update files from upstream with "make fetch"
tests: tweaks and minimal improvements to t/insthook.sh
typofix: in comments in t/extra2.sh
tests: fix botched cross-reference in a heading comment
compat: reinstate support for obsolete $(INCLUDES) variable
automake: refactoring: factor out common cpp-like flags
NEWS (mint): reflect new Automake versioning scheme
NEWS (master): reflect new Automake versioning scheme
Add missing '$' for variable expansion in depout.m4
maintcheck: avoid spurious failure
perl: perl subroutine prototypes are problematic, don't use them
fixup: one stray reference to older versioning scheme
preproc: enhance and extend tests
preproc: add support for relative names in included fragments
+ Non-trivial extra changes:
* automake.in (@cpplike_flags): Use $(AM_DEFAULT_INCLUDES), not
$(DEFAULT_INCLUDES). Do not support $(INCLUDES).
(generate_makefile): User definition of $(INCLUDES) causes a fatal
error, not a warning.
* maint:
INSTALL: regen
sync: update files from upstream with "make fetch"
tests: tweaks and minimal improvements to t/insthook.sh
typofix: in comments in t/extra2.sh
tests: fix botched cross-reference in a heading comment
compat: reinstate support for obsolete $(INCLUDES) variable
Since INCLUDES and AM_CPPFLAGS can be both used at the same time in a
single project, and interact in a non-obvious way, switching away from
INCLUDES is, unfortunately, not simply a matter of doing a mindless
INCLUDES -> AM_CPPFLAGS substitution. In fact, the transition from a
"INCLUDES + CPPFLAGS" setup to a "AM_CPPFLAGS only" setup could cause
subtle bugs to sneak into the build systems of the client packages
doing the transition. Forcing this risk upon our users is definitely
not worth the small enhancement in consistency and cleanliness that
the removal of INCLUDES would give us.
For a more extended rationale and related discussions, see:
<http://lists.gnu.org/archive/html/automake/2013-02/msg00001.html>
* automake.in: Re-introduce support for INCLUDES (its use will cause
warnings in the 'obsolete' category rather than fatal errors).
* doc/automake.texi: Adjust to re-add mention of INCLUDES.
* t/includes-no-more.sh: Rename ...
* t/includes-deprecation.sh: ... like this, and adjust.
* t/list-of-tests.mk: Update.
* t/warnopts.sh: Minor fixlet while at it.
Suggested-by: Peter Rosin <peda@lysator.liu.se> Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
automake: refactoring: factor out common cpp-like flags
* automake.in (@cpplike_flags): In this new variable...
(C, C++, Objective C, Objective C++, Unified Parallel C, Preprocessed
Assembler, Preprocessed Fortran, Preprocessed Fortran 77): ... to be
used by registration (with the 'register_language' subroutine) of these
languages.
This is a refactoring meant to simplify future changes; no semantic
change is intended.
NEWS (master): reflect new Automake versioning scheme
The next minor Automake version will be 1.14 (not 1.13.2 -- that will
be the next bug-fixing version). And the next major Automake version
will be 2.0.
* maint:
Add missing '$' for variable expansion in depout.m4
maintcheck: avoid spurious failure
perl: perl subroutine prototypes are problematic, don't use them
fixup: one stray reference to older versioning scheme
* t/preproc-errmsg.sh: Here, breaking up a sed command to avoid spuriously
triggering a failure in the 'sc_tests_logs_duplicate_prefixes' maintainer
check.
perl: perl subroutine prototypes are problematic, don't use them
Basically, in perl, "subroutine prototypes" are not prototypes at all;
rather, they are a trick to allow user-defined subroutines that behave
like perl built-in functions. For example, prototyped subroutines can
be called without parentheses, and can impose context on their arguments.
Such semantics can be useful in some selected situations, but might also
easily cause unexpected and harmful behaviours and side effects if we
try to use perl prototypes as we would use C prototypes.
See the excellent article "Far More than Everything You've Ever Wanted
to Know about Prototypes in Perl" by Tom Christiansen for more detailed
information:
It is important to note that modern perl allows a non-predeclared
subroutine to be called without the '&' character, as long as its
call uses proper parentheses:
foo 'str', 2; # will trigger errors if foo is not predeclared
foo('str', 2); # ok even if foo is not predeclared
&foo('str', 2); # ditto; but the '&' is old-style and redundant
Note also that the prototype indicating "no argument":
sub func() { ... }
can actually be useful, and has no discernible downsides, so we'll
keep using it where it makes sense.
Also, in few, selected cases, we *want* to have subroutines behave like
perl builtins (e.g., we want the 'append_exeext' function to be able
to take a code block as first argument). In such cases, we will of
course continue to make use of perl subroutine prototypes.
Let's finally see an example that might clarify the kind of problems the
use of subroutine prototypes in perl can cause. This is just scratching
the surface; there are several other aspects, typically subtler and more
dangerous, that are not touched here.
If you have the prototyped subroutine definition:
sub foo ($@)
{
my $s = shift;
print "SCALAR: $s\n";
print "ARRAY: @_\n";
}
and call 'foo' in code like:
@list = (-1, 0, 1);
foo(@list);
you won't get a compile-time nor a runtime error (as a naive interpretation
of the "prototype" characterization would let you think). Rather, the
prototype will cause the array '@list' will be coerced into scalar context
before being passed too 'foo', which means that its *length* (3) will be
passed to 'foo' as first argument; and since no further arguments are
present after '@list', that *void* will be coerced to an empty list before
being passed to 'foo'.
So code above will have the result of printing:
SCALAR: 3
ARRAY:
Quite tricky, and definitely a behaviour we don't want to rely on.
* automake.in: Delete most subroutine prototypes. Fix few of the
remaining ones. Related minor simplifications and adjustments.
* lib/gen-perl-protos: Adjust.
* master:
maint: more adjustments to the new versioning scheme
aclocal: fix for more-than-once specified directories
aclocal: just warn if the primary local m4 dir doesn't exist (don't error)
coverage: expose automake bug#13760
tests: refactor/enhance tests about make dry-run mode
maint: describe new versioning and branching scheme, and adjust to it
cosmetics: fix some "docstring-like" comments in automake
+ t/make-dryrun.tap: Several adjustments, since this test had diverged
quite significantly from the version in mainline Automake. Particularly
relevant is the fact that Automake-NG seems immune to bug#13760, so that
some tests that are returning XFAIL in mainline automake succeeds for
Automake-NG.
* maint:
maint: more adjustments to the new versioning scheme
aclocal: fix for more-than-once specified directories
aclocal: just warn if the primary local m4 dir doesn't exist (don't error)
coverage: expose automake bug#13760
tests: refactor/enhance tests about make dry-run mode
maint: describe new versioning and branching scheme, and adjust to it
cosmetics: fix some "docstring-like" comments in automake
* branch-1.13.2:
coverage: expose automake bug#13760
tests: refactor/enhance tests about make dry-run mode
maint: describe new versioning and branching scheme, and adjust to it
Pavel Raiskup [Mon, 11 Feb 2013 12:11:51 +0000 (13:11 +0100)]
aclocal: just warn if the primary local m4 dir doesn't exist (don't error)
Related to automake bug#13514.
Every package which does not need to have the local m4 macro
directory pre-existing in the version control system (because
e.g., it does not have nor need any private m4 macros) would
fail during the "autoreconf -vfi" phase if AC_CONFIG_MACRO_DIRS([m4])
is specified in configure.ac (it could be to instruct tools like
'autopoint' and 'libtoolize' to use 'm4' as the local directory
where to install definitions of their m4 macros, and to instruct
aclocal to look into it). The failure would go like this:
autoreconf: Entering directory `.'
autoreconf: running: aclocal --force
aclocal: error: couldn't open directory 'm4': No such file or directory
autoreconf: aclocal failed with exit status: 1
The problem is that when 'aclocal' is run for the first time during
'autoreconf', the directory 'm4' does not exist yet. It will be
created by e.g., 'libtoolize' or 'autopoint' later on. During the
second 'aclocal' run, the 'm4' directory exists and aclocal does not
complain.
To work around this issue, we degrade the error to a simple warning.
The warning is still quite useful when aclocal is run by hand - so
we are not removing completely.
See also:
<http://lists.gnu.org/archive/html/bug-automake/2013-01/msg00115.html>
<http://lists.gnu.org/archive/html/automake-patches/2010-02/msg00030.html>
<http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=565663>
<https://bugzilla.redhat.com/show_bug.cgi?id=901333>
* aclocal.in (SCAN_M4_DIRS_SILENT, SCAN_M4_DIRS_WARN)
(SCAN_M4_DIRS_ERROR): New constants.
(scan_m4_dirs): Change the second parameter name to $ERR_LEVEL to
better reflect new semantic. Use new constants.
(scan_m4_files): Adjust to reflect the new 'scan_m4_dirs' semantics.
* t/aclocal-macrodir.tap: Adjust.
* t/aclocal-macrodirs.tap: Likewise.
* THANKS: Update.
* NEWS: Likewise.
Suggested-by: Ben Pfaff <blp@cs.stanford.edu> Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
projects / thirdparty / automake.git / log
