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.
This logic was added to libc & libm to get it working again after some
reworks in the CPP handling, but now that that's settled, let's move
this to the common newlib configure logic. This will make it easier
to consolidate all the configure calls into the top-level newlib dir.
This does create a lot of noise in the generate scripts, but that's
because of the ordering of the calls, not because of correctness. We
will try to draw that back down in follow up commits as we modernize
the toolchain calls in here.
This code is a bit more convoluted than it needs to be. GPR_SOURCES
is never set to anything, and the automake checks use negative logic
to add the SP & DP source files to dedicated variables that are only
expanded once. Get rid of the unused variable, use normal boolean
logic, and collapse the source settings into a single variable.
This allows building the libc & libm pages in parallel, and drops
the duplication in the subdirs with the chew/chapter settings.
The unused rules in Makefile.shared are left in place to minimize
noise in the change.
This doesn't migrate all the docs, just the libc's manual (pdf/info).
This is to show the basic form of migrating the chew files.
For subdirs that didn't have any docs, I've stripped their settings
for clarity. If someone wanted to suddenly add docs, they can add
the corresponding Makefile.inc files easily.
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.
Let automake manage whether the objects are included in lib.a. This
fixes failures after to commit 71086e8b2d
("newlib: delete (most) redundant lib_a_CCASFLAGS=$(AM_CCASFLAGS)") due
to automake generating different set of implicit rules, and the code in
here assuming the names of the generated objects.
We've been using both libc_cv_ and newlib_cv_ for our cache vars.
Let's consolidate on newlib_cv_ to avoid conflicts with glibc which
is already using the libc_cv_ prefix.
This isn't strictly necessary, but it makes for much clearer logs as
to what the target is doing, and provides cache vars for anyone who
wants to force the test a different way, and it lets the build cache
its own results when rerunning config.status.
Since commit dcbff9eea7 ("newlib: merge
iconvdata into top-level Makefile"), there is no configure script in
the iconvdata/ subdir, so this call will just issue a warning and not
do anything useful. Punt it.
Restore the call to AC_NO_EXECUTABLES -- I naively assumed in commit
2e9aa5f56c ("newlib: update preprocessor
configure checks") that checking for a preprocessor would not involve
linking code. Unfortunately, autoconf will implicitly check that the
compiler "works" before allowing it to be used, and that involves a
link test, and that fails because newlib provides the C library which
is needed to pass a link test.
There is some code in NEWLIB_CONFIGURE specifically to help mitigate
these, but it's not kicking in here for some reason, so let's just add
the AC_NO_EXECUTABLES call back until we can unwind that custom logic.
Additionally, we have to call AC_PROG_CPP explicitly. This was being
invoked later on, but only in the use_libtool=yes codepath, and that
is almost never enabled.
This code snippet assumed it was only ever run in the top configure
script where srcdir would point to newlib/ which is parallel to the
winsup/ tree. This is incorrect for all of the subdir configure
scripts leading to bad -I flags in $(CC). Switch it over to the
new abs_newlib_basedir which should work in all subdirs.
When we had configure scripts in subdirs, the newlib_basedir value
was computed relative to that, and it'd be the same when used in the
Makefile in the same dir. With many subdir configure scripts removed,
the top-level configure & Makefile can't use the same relative path.
So switch the subdir Makefiles over to abs_newlib_basedir when they
use -I to find source headers.
Do this for all subdirs, even ones with configure scripts and where
newlib_basedir works. This makes the code consistent, and avoids
surprises if the configure script is ever removed in the future as
part of merging to the higher level.
Some of the subdirs were using -I$(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.
Commit dd23de27c8 ("newlib: libc: install
CRT0 straight out of subdir") got rid of the libc/sys/ intermediate for
copying the file up, but the top-level newlib/ dir was still expecting
a libc/crt0.o to exist so it could install. Update that to also look
for the crt0 file directly under libc/ like we already do for crt1.
The work to merge libc/machine/ up a dir lost the stub doc targets.
So when libc/ recursed into machine/, it would stop going deeper as
the doc rules were empty. But now that libc/ goes directly into the
libc/machine/$arch/ and those have never had doc stubs, the build
fails. Add a quick hack to the top dir to ignore all machine/$arch/
dirs when generating docs. A follow up series will delete all of
this code as it merges all the doc rules into the top newlib dir.
We use the common config-ml.in for configure, so switch the makefile
over to the common multilib.am. It's almost exactly the same code,
but there are two differences:
* Common code hooks install-exec-local for install-multi, but newlib
doesn't currently install any executables, so that doesn't fire.
Newlib already has install-data-local that inlined install-multi,
so switch that to the common install-multi.
* Common code doesn't provide a check-multi at all. Keep ours for
now. Some day common code might get it. Or not. Who knows.
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.
The sys configure scripts are almost all effectively stub scripts that
pass the higher level options to its own makefile. The phoenix & linux
ones are a bit more complicated with nested subdirs, so those have been
left alone for now. Plus, I don't really have a way of testing them.
There's no need to have a sys/ subdir just to copy the sys/$arch/crt0.o
up to sys/crt0.o, and then have libc/ copy sys/crt0.o up again. Just
have libc/ refer to sys/$arch/crt0.o directly and drop the intermediate
makefile entirely.
The sys/{configure,Makefile} files exist to fan out to the specific
sys/$arch/ subdir, and to possibly generate a crt0. We already have
all that same info in the libc/ dir itself, so by moving the recursive
configure and make calls into it, we can cut off some of this logic
entirely and save the overhead.
For arches that don't have a sys subdir, it means they can skip the
logic entirely.
The sys subdir itself is kept for the crt0 logic, for now. We'll try
and clean that up next.
The machine/{configure,Makefile} files exist only to fan out to the
specific machine/$arch/ subdir. We already have all that same info
in the libc/ dir itself, so by moving the recursive configure and
make calls into it, we can cut off this logic entirely and save the
overhead.
For arches that don't have a machine subdir, it means they can skip
the logic entirely. Although there's prob not too many of those.
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.
The machine/{configure,Makefile} files exist only to fan out to the
specific machine/$arch/ subdir. We already have all that same info
in the libm/ dir itself, so by moving the recursive configure and
make calls into it, we can cut off this logic entirely and save the
overhead.
For arches that don't have a machine subdir, it means they can skip
the logic entirely.
This makes the makefile logic a bit cleaner so we don't have two
files maintaining lists of sources & objects. Since the logic is
tied to cpu capabilities, past those boolean settings down from
the configure logic to the makefile logic.
This will also make it easier to throw away the configure script
in a follow up commit and just keep the makefile.
The nds32 & spu dirs are using compile tests to look for some
preprocessor defines, but we don't need to compile the code,
just preprocess it. So switch to AC_PREPROC_IFELSE.
The sh dir is using a preprocessor test via grep, but let's
switch it to AC_PREPROC_IFELSE too to be consistent.
This should allow us to drop the uncommon AC_NO_EXECUTABLES call.
This was added decades ago, but the commit message lacks any
explanation, and it was unused when it was merged. It's still
unused today. So punt it all.
Generating these files is very cheap, so let's just do it all the time.
This makes the build logic simpler, and keeps errors for slipping in in
codepaths that are not well tested. Creating these files doesn't mean
they'll be included in the manual implicitly.
For example, some of the nano stdio files break documentation because
they don't have any chew directives in them. But no one noticed since
that code path is rarely enabled. So drop the _i and _float def files.
This is already handled by autotools for us automatically. You can
tell as the generated output is exactly the same other than deleting
a few blank lines.
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.
The current newlib multilib logic is almost exactly the same as the
config/multi.m4, and the differences should be minor, so switch over
to that to delete custom logic on ourside.
Now that we require a recent version of autoconf, we can rely on this
macro working. This change was already made to libm, but these other
dirs were missed as I didn't notice it being duplicated in 3 places.
Now that newlib.hin has been brought up to date and all of its defines
are produced by configure, we can switch it to using autoheader without
manual editing. This relies on a few pieces:
* Moving the header & footer into configure.ac via AH_TOP & AH_BOTTOM.
* Running a post-process step on newlib.h to delete all the defines we
didn't export ourselves. Basically, anything without a _ prefix.
This will leave behind some spurious comments in newlib.h related to
the defines we filtered out, but should be harmless, so it's probably
not worth the effort to construct a more complicated sed expression to
also strip those out.
The list of iconv to/from defines is hand maintained in newlib.hin.
Lets leverage mkdeps.pl to generate this list automatically from the
list of known encodings. The newlib.hin list is up-to-date, so the
list in iconv.m4 matches the list already generated.
This was added to configure, but never to the header file. Nothing
uses this currently, so it's not a big deal (as all the dynamic logic
is via automake conditionals), but might as well restore it now to
keep autoheader output in sync.
Mike Frysinger
Cyril Yared