The nano malloc build broke with:
Commit 357d7fcc6
In <stdio.h> provide only necessary types
The above commit exposed a latent missing-header bug:
newlib/libc/stdlib/nano-mallocr.c:220:33: error: ‘uintptr_t’ undeclared (first use in this function)
Fix by including <stdint.h>.
Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
By including sys/_stdint.h, all types from stdint.h are
exposed even if stdint.h isn't pulled in explicitely. Include
<machine/_default_types.h instead. Fix up newlib and Cygwin
files which rely on stdint.h types, too.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Convert all the libc/ subdir makes into the top-level Makefile. This
allows us to build all of libc 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 libc.a. The
machine override logic is maintained though by way of Makefile include
ordering, and source file accumulation in libc_a_SOURCES.
There's a few dummy.c files that are no longer necessary since we aren't
doing the lib.a accumulating, so punt them.
The winsup code has been pulling the internal newlib ssp library out,
but that doesn't exist anymore, so change that to pull the objects.
Rather than define per-object rules in the Makefile, have small files
that define & include the right content. This simplifies the build
rules, and makes understanding the source a little easier (imo) as it
makes all the subdirs behave the same: you have 1 source file and it
produces 1 object. It's also about the same amount of boiler plate,
without having to define custom build rules that can fall out of sync.
This will also be important as we merge the libc.a build into the top
dir since it relies on a single flat list of objects for overrides.
Also take the opportunity to clean up the unnecessary header deps in
here. Automake provides dependency generation for free now.
This file is a little confusing: it provides all of the mallocr logic,
but is compiled multiple times to produce a unique symbol each time.
For example, building mallocr.c with -DDEFINE_FREER produces freer.o
that only defines _free_r(). This is fine for most symbols, but it's
a little confusing when defining mallocr itself -- we produce a file
with the same symbol name, but we still need -DDEFINE_MALLOCR. In
order to move the logic from the build rules to source files, using
mallocr.c both as a multiplexer and for defining a single symbol is a
bit tricky. It's possible (if we add a lot of redundant preprocessor
checks to mallocr.c, or we add complicated build flags just for this
one files), but it's easier if we simply rename this to a dedicated
file. So let's do that.
We do this as a dedicated commit because the next one will create a
new mallocr.c file and git's automatic diff algorithms can handle
trivial renames, but it can't handle renames+creates in the same
commit.
Simplify the build system logic a bit by moving the mallocr.c ->
nano-mallocr.c redirection from the Makefile to the source files.
This allows for consistent object name usage regardless of the
configuration options used in case a machine dir wants to define
its own override.
Since we already set up _LIBC to indicate source files are building
for newlib, we don't need this malloc-specific symbol. Convert it
over to simplify the build a bit.
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.
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.
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.
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.
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.
This define is only used by newlib internally, so stop exporting it
as HAVE_INITFINI_ARRAY since this can conflict with defines packages
use themselves.
We don't really need to add _ to HAVE_INIT_FINI too since it isn't
exported in newlib.h, but might as well be consistent here.
We can't (easily) add this to newlib_cflags like HAVE_INIT_FINI is
because this is based on a compile-time test in the top configure,
not on plain shell code in configure.host. We'd have to replicate
the test in every subdir in order to have it passed down.
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.
The 'cygnus' option was removed from automake 1.13 in 2012, so the
presence of this option prevents that or a later version of automake
being used.
A check-list of the effects of '--cygnus' from the automake 1.12
documentation, and steps taken (where possible) to preserve those
effects (See also this thread [1] for discussion on that):
[1] https://lists.gnu.org/archive/html/bug-automake/2012-03/msg00048.html
1. The foreign strictness is implied.
Already present in AM_INIT_AUTOMAKE in newlib/acinclude.m4
2. The options no-installinfo, no-dependencies and no-dist are implied.
Already present in AM_INIT_AUTOMAKE in newlib/acinclude.m4
Future work: Remove no-dependencies and any explicit header dependencies,
and use automatic dependency tracking instead. Are there explicit rules
which are now redundant to removing no-installinfo and no-dist?
3. The macro AM_MAINTAINER_MODE is required.
Already present in newlib/acinclude.m4
Note that maintainer-mode is still disabled by default.
4. Info files are always created in the build directory, and not in the
source directory.
This appears to be an error in the automake documentation describing
'--cygnus' [2]. newlib's info files are generated in the source
directory, and no special steps are needed to keep doing that.
[2] https://lists.gnu.org/archive/html/bug-automake/2012-04/msg00028.html
5. texinfo.tex is not required if a Texinfo source file is specified.
(The assumption is that the file will be supplied, but in a place that
automake cannot find.)
This effect is overriden by an explicit setting of the TEXINFO_TEX
variable (the directory part of which is fed into texi2X via the
TEXINPUTS environment variable).
6. Certain tools will be searched for in the build tree as well as in the
user's PATH. These tools are runtest, expect, makeinfo and texi2dvi.
For obscure automake reasons, this effect of '--cygnus' is not active
for makeinfo in newlib's configury.
However, there appears to be top-level configury which selects in-tree
runtest, expect and makeinfo, if present. So, if that works as it
appears, this effect is preserved. If not, this may cause problem if
anyone is building those tools in-tree.
This effect is not preserved for texi2dvi. This may cause problems if
anyone is building texinfo in-tree.
If needed, explicit checks for those tools looking in places relative to
$(top_srcdir)/../ as well as in PATH could be added.
7. The check target doesn't depend on all.
This effect is not preseved. The check target now depends on the all
target.
This concern seems somewhat academic given the current state of the
testsuite.
Also note that this doesn't touch libgloss.
- This patch uses gdtoa imported from OpenBSD if newlib configure
option "--enable-newlib-use-gdtoa=no" is NOT specified. gdtoa
provides more accurate output and faster conversion than legacy
ldtoa, while it requires more heap memory.
- If the number has large integer part and small fraction part is
specified in output format, e.g. printf("%.3f", sqrt(2)*1e60);,
valid output digits were insufficient. This patch fixes the issue.
https://cygwin.com/pipermail/cygwin/2021-November/249930.html
reported a regression introduce by using a dynamically sized local
char array in favor of a statically sized array.
Fix this by reverting to a statically sized array, using a small
buffer on the stack for a reasonable number of requested digits, a
big mallocated buffer otherwise. This should work for small targets
as well, given that malloc is used in printf anyway right now.
This is *still* hopefully just a temporary measure, unless somebody
actually provides a new ldtoa.
Fixes: 4d90e53359 ("ldtoa: fix dropping too many digits from output")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
ldtoa cuts the number of digits it returns based on a computation of
number of supported bits (144) divide by log10(2). Not only is the
integer approximation of log10(2) ~= 8/27 missing a digit here, it
also fails to take really small double and long double values into
account.
Allow for the full potential precision of long double values. At the
same time, change the local string array allocation to request only as
much bytes as necessary to support the caller-requested number of
digits, to keep the stack size low on small targets.
In the long run a better fix would be to switch to gdtoa, as the BSD
variants, as well as Mingw64 do.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
When newlib is configured with --enable-newlib-reent-check-verify,
the assert macro is already defined in the nano-mallocr.c compile unit.
Contributed by STMicroelectronics
Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@st.com>
_strtod_l as well as the gethex function both fetch the decimal point
from the current LC_NUMERIC locale info. This pulls in _C_numeric_locale
unconditionally even on targets not supporting locales at all.
Another problem is that strtod.c and gdtoa-gethex.c are ELIX 1, while
locale information in general isn't. This leads to potential build
breakage on bare metal targets.
Fix this by setting the decimal point to "." on all targets not
defining __HAVE_LOCALE_INFO__.
While at it, const'ify the entire local decimal point info in the
affected functions.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
The C standard says that errno may acquire the value ERANGE if the
result from strtod underflows. According to IEEE 754, underflow occurs
whenever the value cannot be represented in normalized form.
Newlib is inconsistent in this, setting errno to ERANGE only if the
value underflows to zero, but not for denorm values, and never for hex
format floats.
This patch attempts to consistently set errno to ERANGE for all
'underflow' conditions, which is to say all values which are not
exactly zero and which cannot be represented in normalized form.
This matches glibc behavior, as well as the Linux, Mac OS X, OpenBSD,
FreeBSD and SunOS strtod man pages.
Signed-off-by: Keith Packard <keithp@keithp.com>
The only reason why it is tough for us to use nano malloc
is because of the small shortcoming where nano_malloc()
splits a bigger chunk from the free list into two pieces
while handing back the second one (the tail) to the user.
This is error prone and especially bad for smaller heaps,
where nano malloc is supposed to be superior. The normal
malloc doesn't have this issue and we need to use it even
though it costs us ~2k bytes compared to nano-malloc.
The problem arise especially after giving back _every_
malloced memory to the heap and then starting to exercise
the heap again by allocating something small. This small
item might split the whole heap in two equally big parts
depending on how the heap has been exercised before.
I have uploaded the smallest possible application
(only tested on ST and Nordic devices) to show the issue
while the real customer applications are far more complicated:
https://drive.google.com/file/d/1kfSC2KOm3Os3mI7EBd-U0j63qVs8xMbt/view?usp=sharing
The application works like the following pseudo code,
where we assume a heap of 100 bytes
(I haven't taken padding and other nitty and gritty
details into account. Everything to simplify understanding):
void *ptr = malloc(52); // We get 52 bytes and we have
// 48 bytes to use.
free(ptr); // Hand back the 52 bytes to nano_malloc
// This is the magic line that shows the issue of
// nano_malloc
ptr = malloc(1); // Nano malloc will split the 52 bytes
// in the free list and hand you a pointer
// somewhere in the
// middle of the heap.
ptr2 = malloc(52); // Out of memory...
I have done a fix which hands back the first part of the
splitted chunk. Once this is fixed we obviously
have the 1 byte placed in position 0 of the heap instead
of somewhere in the middle.
However, this won't let us malloc 52 new bytes even though
we potentially have 99 bytes left to use in the heap. The
reason is that when we try to do the allocation,
nano-malloc looks into the free list and sees a 51 byte
chunk to be used.
This is not big enough so nano-malloc decides to call
sbrk for _another_ 52 bytes which is not possible since
there is only 48 bytes left to ask for.
The solution for this problem is to check if the last
item in the free list is adjacent to sbrk(0). If it is,
as it is in this case, we can just ask sbrk for the
remainder of what is needed. In this case 1 byte.
NB! I have only tested the solution on our ST device.
So far the build mechanism in newlib only allowed to either define
machine-specific headers, or headers shared between all machines.
In some cases, architectures are sufficiently alike to share header
files between them, but not with other architectures. A good example
is ix86 vs. x86_64, which share certain traits with each other, but
not with other architectures.
Introduce a new configure variable called "shared_machine_dir". This
dir can then be used for headers shared between architectures.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Without this, for a bare-iron/simulator target such as cris-elf,
you'll see, at newlib build time:
/x/gccobj/./gcc/xgcc -B/x/gccobj/./gcc/ <many options elided> -c -o lib_a-aligned_alloc.o \
`test -f 'aligned_alloc.c' || echo '/y/newlib/libc/stdlib/'`aligned_alloc.c
/y/newlib/libc/stdlib/aligned_alloc.c: In function 'aligned_alloc':
/y/newlib/libc/stdlib/aligned_alloc.c:35:10: warning: implicit declaration of function \
'_memalign_r' [-Wimplicit-function-declaration]
35 | return _memalign_r (_REENT, align, size);
| ^~~~~~~~~~~
The overflow check in mEMALIGn erroneously checks for INT_MAX,
albeit the input parameter is size_t. Fix this to check for
__SIZE_MAX__ instead. Also, it misses to check the req against
adding the alignment before calling mALLOc.
While at it, add out-of-bounds checks to pvALLOc, nano_memalign,
nano_valloc, and Cygwin's (unused) dlpvalloc.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Sebastian Huber
Matt Joyce
Dimitar Dimitrov
Corinna Vinschen
Mike Frysinger
Cyril Yared
Jon Turney
Takashi Yano
Torbjorn SVENSSON via Newlib
Keith Packard
Ola Olsson
Hans-Peter Nilsson
Corinna Vinschen