Now that these functions are behind _COSMO_SOURCE there's no reason for
having the ugly underscore anymore. To use these functions, you need to
pass -mcosmo to cosmocc.
The WIN32 CreateProcess() function does not require an .exe or .com
suffix in order to spawn an executable. Now that we have Cosmo bash
we're no longer so dependent on the cmd.exe prompt.
- Write some more unit tests
- memcpy() on ARM is now faster
- Address the Musl complex math FIXME comments
- Some libm funcs like pow() now support setting errno
- Import the latest and greatest math functions from ARM
- Use more accurate atan2f() and log1pf() implementations
- atoi() and atol() will no longer saturate or clobber errno
Multiple projects I care about make the assumption that this isn't a
system call that sleeps for a particular number of nanonseconds, but
rather a function that parks processes on kernel scheduler quantums.
Anyone who wants the old behavior should use cosmo_clock_nanosleep()
* Fix reading the same symbol twice when using `{f,}scanf()`
PR #924 appears to use `unget()` subtly incorrectly when parsing
floating point numbers. The rest of the code only uses `unget()`
immediately followed by `goto Done;` to return back the symbol that
can't possibly belong to the directive we're processing.
With floating-point, however, the ungot characters could very well
be valid for the *next* directive, so we will essentially read them
twice. It can't be seen in `sscanf()` tests because `unget()` is a
no-op there, but the test I added for `fscanf()` fails like this:
...
EXPECT_EQ(0xDEAD, i1)
need 57005 (or 0xdead) =
got 908973 (or 0x000ddead)
...
EXPECT_EQ(0xBEEF, i2)
need 48879 (or 0xbeef) =
got 769775 (or 0x000bbeef)
This means we read 0xDDEAD instead of 0xDEAD and 0xBBEEF instead of
0xBEEF. I checked that both musl and glibc read 0xDEAD/0xBEEF, as
expected.
Fix the failing test by removing the unneeded `unget()` calls.
* Don't read invalid floating-point numbers in `*scanf()`
Currently, we just ignore any errors from `strtod()`. They can
happen either because no valid float can be parsed at all, or
because the state machine recognizes only a prefix of a valid
floating-point number.
Fix this by making sure `strtod()` parses everything we recognized,
provided it's non-empty. This requires to pop the last character
off the FP buffer, which is supposed to be parsed by the next
`*scanf()` directive.
* Make `%c` parsing in `*scanf()` respect the C standard
Currently, `%c`-style directives always succeed even if there
are actually fewer characters in the input than requested.
Before the fix, the added test fails like this:
...
EXPECT_EQ(2, sscanf("ab", "%c %c %c", &c2, &c3, &c4))
need 2 (or 0x02 or '\2' or ENOENT) =
got 3 (or 0x03 or '\3' or ESRCH)
...
EXPECT_EQ(0, sscanf("abcd", "%5c", s2))
need 0 (or 0x0 or '\0') =
got 1 (or 0x01 or '\1' or EPERM)
musl and glibc pass this test.
Sometimes we need to interact with code that wasn't compiled using
`-fno-omit-frame-pointer`. For example, if a function pointer gets
passed and called by a foreign function, linked by cosmo_dlopen().
Function call tracing will now detect backtrace pointer corruption
and simply reduce the indentation level back to zero, as a result.
This change upgrades to GCC 12.3 and GNU binutils 2.42. The GNU linker
appears to have changed things so that only a single de-duplicated str
table is present in the binary, and it gets placed wherever the linker
wants, regardless of what the linker script says. To cope with that we
need to stop using .ident to embed licenses. As such, this change does
significant work to revamp how third party licenses are defined in the
codebase, using `.section .notice,"aR",@progbits`.
This new GCC 12.3 toolchain has support for GNU indirect functions. It
lets us support __target_clones__ for the first time. This is used for
optimizing the performance of libc string functions such as strlen and
friends so far on x86, by ensuring AVX systems favor a second codepath
that uses VEX encoding. It shaves some latency off certain operations.
It's a useful feature to have for scientific computing for the reasons
explained by the test/libcxx/openmp_test.cc example which compiles for
fifteen different microarchitectures. Thanks to the upgrades, it's now
also possible to use newer instruction sets, such as AVX512FP16, VNNI.
Cosmo now uses the %gs register on x86 by default for TLS. Doing it is
helpful for any program that links `cosmo_dlopen()`. Such programs had
to recompile their binaries at startup to change the TLS instructions.
That's not great, since it means every page in the executable needs to
be faulted. The work of rewriting TLS-related x86 opcodes, is moved to
fixupobj.com instead. This is great news for MacOS x86 users, since we
previously needed to morph the binary every time for that platform but
now that's no longer necessary. The only platforms where we need fixup
of TLS x86 opcodes at runtime are now Windows, OpenBSD, and NetBSD. On
Windows we morph TLS to point deeper into the TIB, based on a TlsAlloc
assignment, and on OpenBSD/NetBSD we morph %gs back into %fs since the
kernels do not allow us to specify a value for the %gs register.
OpenBSD users are now required to use APE Loader to run Cosmo binaries
and assimilation is no longer possible. OpenBSD kernel needs to change
to allow programs to specify a value for the %gs register, or it needs
to stop marking executable pages loaded by the kernel as mimmutable().
This release fixes __constructor__, .ctor, .init_array, and lastly the
.preinit_array so they behave the exact same way as glibc.
We no longer use hex constants to define math.h symbols like M_PI.
- Introduce portable sched_getcpu() api
- Support GCC's __target_clones__ feature
- Make fma() go faster on x86 in default mode
- Remove some asan checks from core libraries
- WinMain() now ensures $HOME and $USER are defined
1. `libc/isystem/complex.h` (included when you do `#include <complex.h>`)
defines `_COMPLEX_H`, and then proceeds to include `libc/complex.h`,
which contains the actual complex-related declarations. However, they
are *also* guarded by `_COMPLEX_H` and hence effectively ignored.
Fix this by changing `_COMPLEX_H` to `COSMOPOLITAN_LIBC_COMPLEX_H_`,
which is consistent with what the other headers (such as `math.h`) do.
2. Cosmopolitan could only support IPv4 multicast requests for sockets,
since a declaration for `struct ipv6_mreq` was missing. Add support
for IPv6, too, by adding the missing declaration.
- Let OpenMP be usable via cosmocc
- Let libunwind be usable via cosmocc
- Make X86_HAVE(AVXVNNI) work correctly
- Avoid using MAP_GROWSDOWN on qemu-aarch64
- Introduce in6addr_any and in6addr_loopback
- Have thread stacks use MAP_GROWSDOWN by default
- Ask OpenMP to not use filesystem to manage threads
- Make NI_MAXHOST and NI_MAXSERV available w/o _GNU_SOURCE
We recently broke MODE=dbg support when we added C++ exception support.
This change adds the missing UBSAN interfaces, needed to get it working
again. Some of the ASAN checking in the SJLJ guts needed to be disabled
since I doubt anyone's combined the two features until now.
Embedding Blink builds in Cosmo executables was a failed experiment. It
turned out to be easier than expected to let the mono repo have support
for multiple architectures. Blink still works great; it's supported and
recommended; just please use it as a separate program. For example, you
can use Blink to run Cosmo binaries on architectures like i486 / s390x.
If you install qemu-user from apt then glibc links a lot of address
space bloat that causes pthread_create() to ENOMEM (a.k.a. EAGAIN).
Boosting the virtual memory quota from 512m to 2048m will hopefully
future proof the build for the future, as Linux distros get fatter.
Please note this only applies to MODE=aarch64 on x86_64 builds when
you're using QEMU from Debian/Ubuntu rather than installing the one
cosmo provides in third_party/qemu/qemu-aarch64.gz. This change may
also be useful to people who are using the host compiler toolchain.
- `__cxa_*` runtime functions are expected to be in the `abi` namespace,
which is currently an alias for `__cxxabiv1`.
- Rely on the header provided by `libcxxabi` for functions that we do
not implement ourselves anymore.
This will help C++ code that uses exceptions to be tinier. For example,
this change shaves away 1000 lines of assembly code from LLVM's libcxx,
which is 0.7% of all assembly instructions in the entire library.
We now store values in jmp_buf where the compiler wants them to be. This
fixes code that calls __builtin_setjmp() and __builtin_longjmp() such as
libunwind. All libcxxabi tests are now passing on ARM64.
See #1076
Renaming gc() to _gc() was a mistake since the better thing to do is put
it behind the _COSMO_SOURCE macro. We need this change because I haven't
wanted to use my amazing garbage collector ever since we renamed it. You
now need to define _COSMO_SOURCE yourself when using amalgamation header
and cosmocc users need to pass the -mcosmo flag to get the gc() function
Some other issues relating to cancelation have been fixed along the way.
We're also now putting cosmocc in a folder named `.cosmocc` so it can be
more safely excluded by grep --exclude-dir=.cosmocc --exclude-dir=o etc.
* third_party: Add libcxxabi
Added libcxxabi from LLVM 17.0.6
The library implements the Itanium C++ exception handling ABI.
* third_party/libcxxabi: Enable __cxa_thread_atexit
Enable `__cxa_thread_atexit` from libcxxabi.
`__cxa_thread_atexit_impl` is still implemented by the cosmo libc.
The original `__cxa_thread_atexit` has been removed.
* third_party/libcxx: Build with exceptions
Build libcxx with exceptions enabled.
- Removed `_LIBCPP_NO_EXCEPTIONS` from `__config`.
- Switched the exception implementation to `libcxxabi`. These two files
are taken from the same `libcxx` version as mentioned in `README.cosmo`.
- Removed `new_handler_fallback` in favor of `libcxxabi` implementation.
- Enable `-fexceptions` and `-frtti` for `libcxx`.
- Removed `THIRD_PARTY_LIBCXX` dependency from `libcxxabi` and
`libunwind`. These libraries do not use any runtime `libcxx` functions,
just headers.
* libc: Remove remaining redundant cxa functions
- `__cxa_pure_virtual` in `libcxxabi` is also a stub similar to the
existing one.
- `__cxa_guard_*` from `libcxxabi` is used instead of the ones from
Android.
Now there should be no more duplicate implementations.
`__cxa_thread_atexit_impl`, `__cxa_atexit`, and related supporting
functions, are still left to other libraries as in `libcxxabi`.
`libcxxabi` is also now added to `cosmopolitan.a` to make up for the
removed functions.
Affected in-tree libraries (`third_party/double-conversion`) have been
updated.
The AMD HIP SDK for Linux ships prebuilt DSOs with an RWX PT_GNU_STACK
since old versions of GCC made it nearly impossible to build artifacts
where that wasn't the case, however modern glibc systems will flat out
refuse to link RWX DSOs from an execuatble that uses PT_GNU_STACK = RW
