Convert all the libm/ subdir makes into the top-level Makefile. This
allows us to build all of libm from the top Makefile without using any
recursive make calls. This is faster and avoids the funky lib.a logic
where we unpack subdir archives to repack into a single libm.a. The
machine override logic is maintained though by way of Makefile include
ordering, and source file accumulation in libm_a_SOURCES.
One thing to note is that this will require GNU Make because of:
libm_a_CFLAGS = ... $(libm_a_CFLAGS_$(subst /,_,$(@D)))
This was the only way I could find to supporting per-dir compiler
settings, and I couldn't find a POSIX compatible way of transforming
the variable content. I don't think this is a big deal as other
Makefiles in the tree are using GNU Make-specific syntax, but I call
this out as it's the only one so far in the new automake code that
I've been writing.
Automake doesn't provide precise control over the output object names
(by design). This is fine by default as we get consistent names in all
the subdirs: libm_a-<source>.o. But this relies on using the same set
of compiler flags for all objects. We currently compile libm/common/
with different optimizations than the rest.
If we want to compile objects differently, we can create an intermediate
archive with the subset of objects with unique flags, and then add those
objects to the main archive. But Automake will use a different prefix
for the objects, and thus we can't rely on ordering to override.
But if we leverage $@, we can turn Automake's CFLAGS into a multiplex
on a per-dir (and even per-file if we wanted) basis. Unfortunately,
since $@ contains /, Automake complains it's an invalid name. While
GNU Make supports this, it's a POSIX extension, so Automake flags it.
Using $(subst) avoids the Automake warning to get a POSIX compliant
name, albeit with a GNU Make extension.
This is used in a bunch of places, but nowhere is it ever set, and
nowhere can I find any documentation, nor can I find any other project
using it. So delete the flags to simplify.
This kills off the last configure script under libm/ and folds it
into the top newlib configure script. The vast majority of logic
was already in the top configure script, so move the little that
is left into a libm/acinclude.m4 file.
This was only ever used for i?86-pc-linux-gnu targets, but that's been
broken for years, and has since been dropped. So clean this up too.
This also deletes the funky objectlist logic since it only existed for
the libtool libraries. Since it was the only thing left in the small
Makefile.shared file, we can punt that too.
Now that we use AC_NO_EXECUTABLES, and we require a recent version of
autoconf, we don't need to define our own copies of these macros. So
switch to the standard AC_PROG_CC.
When we had configure scripts in subdirs, the newlib_basedir value
was computed relative to that, and it'd be the same when used in the
Makefile in the same dir. With many subdir configure scripts removed,
the top-level configure & Makefile can't use the same relative path.
So switch the subdir Makefiles over to abs_newlib_basedir when they
use -I to find source headers.
Do this for all subdirs, even ones with configure scripts and where
newlib_basedir works. This makes the code consistent, and avoids
surprises if the configure script is ever removed in the future as
part of merging to the higher level.
Some of the subdirs were using -I$(newlib_basedir)/../newlib/ for
some reason. Collapse those too since newlib_basedir points to the
newlib source tree already.
When using the top-level configure script but subdir Makefiles, the
newlib_basedir value gets a bit out of sync: it's relative to where
configure lives, not where the Makefile lives. Move the abs setting
from the top-level configure script into acinclude.m4 so we can rely
on it being available everywhere. Although this commit doesn't use
it anywhere, just lays the groundwork.
The machine configure scripts are all effectively stub scripts that
pass the higher level options to its own makefile. The only one doing
any custom tests was nds32. The rest were all effectively the same as
the libm/ configure script.
So instead of recursively running configure in all of these subdirs,
generate their makefiles from the top-level configure. For nds32,
deploy a pattern of including subdir logic via m4:
m4_include([machine/nds32/acinclude.m4])
Even its set of checks are very small -- it does 2 preprocessor tests
and sets up 2 makefile conditionals.
Some of the generated machine makefiles have a bunch of extra stuff
added to them, but that's because they were inconsistent in their
configure libtool calls. The top-level has it, so it exports some
new vars to the ones that weren't already.
It's unclear why this was added originally, but assuming it was needed
20 years ago, it shouldn't be explicitly required nowadays. Current
versions of autotools already take care of exporting LDFLAGS to the
Makefile as needed (things are actually getting linked). That's why
the configure diffs show LDFLAGS still here, but shifted to a diff
place in the output list. A few dirs stop exporting LDFLAGS, but
that's because they don't do any linking, only compiling, so it's
correct.
As for the use of $ldflags instead of the standard $LDFLAGS, I can't
really explain that at all. Just use the right name so users don't
have to dig into why their setting isn't respected, and then use a
non-standard name instead. Adjust the testsuite to match.
Since AM_INIT_AUTOMAKE calls AC_PROG_AWK, and some configure.ac
scripts call it too, we end up testing for awk multiple times. If
we change NEWLIB_CONFIGURE to require the macro instead, then it
makes sure it's always expanded, but only once.
While we're here, do the same thing with AC_PROG_INSTALL since it
is also called by AM_INIT_AUTOMAKE, although it doesn't currently
result in duplicate configure checks.
The AC_LIBTOOL_WIN32_DLL macro has been deprecated for a while and code
should call LT_INIT with win32-dll instead. Update the calls to match.
The generated code is noisy not because of substantial differences, but
because the order of some macros change (i.e. instead of calling AS and
then CC, CC is called first and then AS).
Since automake already sets per-library CCASFLAGS to $(AM_CCASFLAGS)
by default, there's no need to explicitly set it here.
Many of these dirs don't have .S files in the first place, so the rule
doesn't even do anything. That can easily be seen when Makefile.in has
no changes as a result.
For the dirs with .S files, the custom rules are the same as the pattern
.S.o rules, so this is a nice cleanup.
The only dir that was adding extra flags (newlib/libc/machine/mn10300/)
to the per-library setting can have it moved to the global AM_CCASFLAGS
since the subdir only has one target. Although the setting just adds
extra debugging flags, so maybe it should be deleted in general.
There are a few dirs that we leave the redundant setting in place. This
is to workaround an automake limitation in subdirs that support building
with & w/out libtool:
https://www.gnu.org/software/automake/manual/html_node/Objects-created-both-with-libtool-and-without.html
This matches what the other GNU toolchain projects have done already.
The generated diff in practice isn't terribly large. This will allow
more use of subdir local.mk includes due to fixes & improvements that
came after the 1.11 release series.
The newlib & libgloss dirs are already generated using autoconf-2.69.
To avoid merging new code and/or accidental regeneration using diff
versions, leverage config/override.m4 to pin to 2.69 exactly. This
matches what gcc/binutils/gdb are already doing.
The README file already says to use autoconf-2.69.
To accomplish this, it's just as simple as adding -I flags to the
top-level config/ dir when running aclocal. This is because the
override.m4 file overrides AC_INIT to first require the specific
autoconf version before calling the real AC_INIT.
Libtool needs to get BSD-format (or MS-format) output out of the system
nm, so that it can scan generated object files for symbol names for
-export-symbols-regex support. Some nms need specific flags to turn on
BSD-formatted output, so libtool checks for this in its AC_PATH_NM.
Unfortunately the code to do this has a pair of interlocking flaws:
- it runs the test by doing an nm of /dev/null. Some platforms
reasonably refuse to do an nm on a device file, but before now this
has only been worked around by assuming that the error message has a
specific textual form emitted by Tru64 nm, and that getting this
error means this is Tru64 nm and that nm -B would work to produce
BSD-format output, even though the test never actually got anything
but an error message out of nm -B. This is fixable by nm'ing *nm
itself* (since we necessarily have a path to it).
- the test is entirely skipped if NM is set in the environment, on the
grounds that the user has overridden the test: but the user cannot
reasonably be expected to know that libtool wants not only nm but
also flags forcing BSD-format output. Worse yet, one such "user" is
the top-level Cygnus configure script, which neither tests for
nor specifies any BSD-format flags. So platforms needing BSD-format
flags always fail to set them when run in a Cygnus tree, breaking
-export-symbols-regex on such platforms. Libtool also needs to
augment $LD on some platforms, but this is done unconditionally,
augmenting whatever the user specified: the nm check should do the
same.
One wrinkle: if the user has overridden $NM, a path might have been
provided: so we use the user-specified path if there was one, and
otherwise do the path search as usual. (If the nm specified doesn't
work, this might lead to a few extra pointless path searches -- but
the test is going to fail anyway, so that's not a problem.)
(Tested with NM unset, and set to nm, /usr/bin/nm, my-nm where my-nm is a
symlink to /usr/bin/nm on the PATH, and /not-on-the-path/my-nm where
*that* is a symlink to /usr/bin/nm.)
ChangeLog
2021-09-27 Nick Alcock <nick.alcock@oracle.com>
PR libctf/27967
* libtool.m4 (LT_PATH_NM): Try BSDization flags with a user-provided
NM, if there is one. Run nm on itself, not on /dev/null, to avoid
errors from nms that refuse to work on non-regular files. Remove
other workarounds for this problem. Strip out blank lines from the
nm output.
This reports common symbols like GNU nm, via a type code of 'C'.
ChangeLog
2021-09-27 Nick Alcock <nick.alcock@oracle.com>
PR libctf/27967
* libtool.m4 (lt_cv_sys_global_symbol_pipe): Augment symcode for
Solaris 11.
AR from older binutils doesn't work with --plugin and rc:
[hjl@gnu-cfl-2 bin]$ touch foo.c
[hjl@gnu-cfl-2 bin]$ ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
[hjl@gnu-cfl-2 bin]$ ./ar --plugin /usr/libexec/gcc/x86_64-redhat-linux/10/liblto_plugin.so rc libfoo.a foo.c
./ar: no operation specified
[hjl@gnu-cfl-2 bin]$ ./ar --version
GNU ar (Linux/GNU Binutils) 2.29.51.0.1.20180112
Copyright (C) 2018 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) any later version.
This program has absolutely no warranty.
[hjl@gnu-cfl-2 bin]$
Check if AR works with --plugin and rc before passing --plugin to AR and
RANLIB.
PR ld/27173
* configure: Regenerated.
* libtool.m4 (_LT_CMD_OLD_ARCHIVE): Check if AR works with
--plugin and rc before enabling --plugin.
config/
PR ld/27173
* gcc-plugin.m4 (GCC_PLUGIN_OPTION): Check if AR works with
--plugin and rc before enabling --plugin.
libiberty/
PR ld/27173
* configure: Regenerated.
zlib/
PR ld/27173
* configure: Regenerated.
The configure scripts were regenerated with 2.69 for the newlib-4.2.0
release in 484d2ebf8d, but the aclocal
files were not. Do that now to avoid confusion between the two as to
which version of autoconf was used.
Since automake deprecated the INCLUDES name in favor of AM_CPPFLAGS,
change all existing users over. The generated code is the same since
the two variables have been used in the same exact places by design.
There are other cleanups to be done, but lets focus on just renaming
here so we can upgrade to a newer automake version w/out triggering
new warnings.
Having symlinks for these files led to an issue reported to the RTEMS
Project that showed up using some tar for native Windows to unpack the
newlib sources. It creates symlinks in the tar file as copies of the
files the symlinks point to. If the links appear in the tar file before
the source exists, it cannot copy the file.
The solution in this patch is to convert the files that are symbolic
links into simple files which include the file they were linked to.
This should be more portable and avoids the symbolinc link problem.
Mike Frysinger
Nick Alcock
Alexander von Gluck IV
H.J. Lu
Samuel Thibault
Jeff Johnston
Jon Turney
Corinna Vinschen
Joel Sherrill