This kills off the last configure script under libc/ and folds it
into the top newlib configure script. The a lot of the logic was
already in the top configure script, so move what's left into a
libc/acinclude.m4 file.
The crt0.o was handled in a subdir-by-subdir basis: it would be compiled
in one (e.g. libc/sys/$arch/), then copied up one level (libc/sys/), then
copied up another (libc/) before finally being copied & installed in the
top newlib dir. The libc/sys/ copy was cleaned up, and then the top dir
was changed to copy it directly out of the libc/sys/$arch/ dir. But the
libc/sys/ copy to libc/ was left behind. Clean that up now too.
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 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.
THe stdio subdir is actually required by the documentation. The
stdio/def is handled dynamically, but libc.texi always expects it
to be included, and fails if it isn't. So making it required when
building docs is safe.
The xdr subdir is handled dynamically, but it doesn't include any
docs, so the dynamic logic isn't (currently) adding any value. So
making it required when building docs is safe.
That leaves: iconv, stdio64, posix, and signal subdirs. The chapters
have a little disclaimer saying they are system-dependent, but even
then, imo having stable manuals regardless of the target is preferable,
and we can add more disclaimer language to these chapters if we want.
This doesn't touch the man page codepaths, just the info/pdf.
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. There were only
three doing custom tests. The rest were all effectively the same as
the libc/ configure script.
So instead of recursively running configure in all of these subdirs,
generate their makefiles from the top-level configure. For the few
unique ones, deploy a pattern of including subdir logic via m4:
m4_include([machine/nds32/acinclude.m4])
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 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.
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.
Mike Frysinger
Jon Turney
Jeff Johnston