After discussion with Rich Felker and other contributors, it's clear
that we want to license this project under the MIT/Expat license.
However, we need to be clear that we're not claiming to license the
binary artifacts, as those retain the licenses of the upstream
projects. Similarly, the patches, to the extent that there is any
copyright interest in them at all, retain the licenses from the
upstream projects.
We've added language in the README and in a new `COPYRIGHT` file to
make all of this clear.
Ref: #25#30#80
with the default --enable-libstdcxx-time, libstdc++'s configure probes
for the existence of a clock_gettime syscall and sets up the time API
implementation to make direct syscalls, presumably as a workaround for
old glibc tucking away the clock_gettime function in librt, which in
turn depends on libpthread. this breaks since struct timespec does not
match the syscall's interface on 32-bit archs.
passing --enable-libstdcxx-time=rt forces different configure paths
that correctly use the public clock_gettime function and librt if
needed.
this issue should be patched in gcc rather than worked around via
configure options, but I'd rather wait to patch until I understand how
to fix it correctly and produce a patch that's acceptable to upstream
and distros.
using slim headers-only version. this change is needed to support all
future versions of musl on 32-bit archs, since prior to 4.16 the
kernel headers had incompatibility with userspace time_t not matching
the kernel's old (32-bit) time_t. support for older headers will be
dropped entirely soon.
both 4.19.90 from official kernel tarball and 4.19.88 from the
sabotage-linux headers-only package are added. the latter should be
preferred unless you have a reason not to, as it's much smaller and
has some patches that improve interaction with musl.
support for all earlier kernel header versions will be dropped soon,
since everything prior to 4.16 has incompatibilities with 32-bit archs
moving to time64.
this is binutils issue 23825, but it's caused by gcc using local-exec
model rather than initial-exec model with the intent of making
binutils generate copy relocations. this is harmful, unnecessary, and
not presently supported by musl (and probably should never be). patch
taken from https://github.com/riscv/riscv-gcc/pull/118.
as maintained in https://github.com/sabotage-linux/kernel-headers .
downloading (and extracting) a 100+ MB kernel source tarball just for
the headers is extremely inefficient.
sabotage linux' kernel-headers tarball provides the same (including
musl compatibility fixes) in ~800 KB.
in order to use it, specify
LINUX_VER = headers-4.4.2-4
in your config.mak.
if LINUX_VER lacks the "headers-" prefix, the official source tarball
will be downloaded as usual.
the default is ordered such that user-provided config variables in
config.mak or on the make command line can still override it.
this is a dubious anti-ROP feature with high cost (file size, load
time, VMA count consumed per library), and historically was broken in
some binutils versions. the ones we use don't seem to be affected, but
it's better to have it off anyway.
new patch: 0017-c++-abi-break.diff fixes a C++ ABI break regression.
0010-static-pie-support.diff was removed as it doesn't apply anymore,
and forward-porting it requires arcane knowledge of GCC details.
the patches 0018 and 0019 have been copied from GCC 7.3.0. the static
pie patch from GCC 6.4.0, renumbered 0020, depends on the reversions
they make.
When the gcc and binutils build trees were separated in defdbb4505,
--enable-deterministic-archives was accidentally left in FULL_GCC_CONFIG.
This had the effect of reverting commit e83fe4b8ce, breaking
reproducible builds (unless it was specified explicitly in config.mak).
Originally added in commit 40d6414f28,
the purpose of the above target definitions was to allow using the
static-only symlink variant of slibtool (i.e. slibtool-static) in
those build steps which required it. Given slibtool's newly added
ability to auto-detect its desired operation mode (shared-only,
static-only, or both), as well as the integration of rlibtool
support in mcm, the aforementioned explicit target definitions
are no longer needed.
Beginning with slibtool version 0.5.26 and the introduction of the
rlibtool symlink (the equivalent of slibtool --heuristics), slibtool
may now be told to automatically detect its desired operation mode
(share-only, static-only, or both) by way of parsing the generated
libtool script which it replaces.
the initial-exec tls model is not valid in any code that might be
dynamically loaded. it usually happens to work on glibc because glibc
reserves some static tls space for late-loaded libraries that need it,
but if it's already been exhausted that will fail. musl does not
support this hack at all, and it's not valid for gcc target libs to be
doing it anywhere, so patch it out entirely rather than just for musl.
the logic for processing the NATIVE var (shortcut for HOST=$(TARGET))
and HOST var took place before inclusion of config.mak, causing NATIVE
not to be honored and wrong BUILD_DIR and OUTPUT defaults to be used
if either was set from config.mak rather than on the make command
line. the current preferred interface is the command line, but the
regression was unintentional.
to fix it, replace the conditional blocks of the makefile with
conditional functions in recursively-expanded variables HOST,
BUILD_DIR, and OUTPUT. this way, assignments to NATIVE or HOST that
take place later in config.mak will affect the resulting values, as
intended.
Generated from within gcc, the above dependency libraries are built with the
--disable-shared libtool option. As with binutils, distinct build steps for
each of the above in litecross/Makefile allow for their correct (static only)
generation by an alternate libtool utility, such as slibtool.
these are not complete/correct in that they do not account for ABI
variants (softfloat and coldfire fpu) in the dynamic linker name, but
I was unable to get gcc's configure to accept --with-float=soft on
m68k to test softfloat and begin figuring out how to do the spec
logic. at some point this needs to be figured out and completed, but
at least the default ABI is available in mcm now.
GCC 6.4.0 has one big advantage over 6.3.0: it is shipped as .tar.xz,
shaving 30 MB from its download size, and also considerably speeding
up the extraction process.
All patches are copies of the GCC 6.3.0 ones, except
0004-posix_memalign.diff which was rebased to apply cleanly.
0014-ubsan-empty-string-fix.diff was removed, since it was upstreamed.
musl uses IEEE quad for long double on s390x. current versions check
for mismatch and hard fail at configure time if the compiler is wrong.
with older versions, mcm silently produced a broken toolchain/libc.
Rich Felker
Travis Cross
Andrew Chambers
rofl0r
Kevin Mark
rofl0r
Michael Forney
midipix
luca
Szabolcs Nagy