This is an experimental proof of concept demo:
make -j8 o//examples/i386.i386.com
o//examples/i386.i386.com --32
echo $? # <-- prints main32's argc parameter
Please note there's no libc support at the moment. This change is just
for fun and shouldn't be interpreted as intent to support. Having this
project on the whole support i386 would be tough because the calling
conventions are so different. There really isn't much in the way of low
hanging fruit opportunities to do something like NOP out REX prefixes
and call it a day. It'd likely need disjoint builds or possibly better
yet really cleverly crafted code generation in //third_party/chibicc!
Another challenge is is that Linux changed its SYSCALL ordinals when it
migrated from i386 to x86_64. Linux used to use the same magic numbers
as everyone else for functions like exit/write/read/etc. BSDs on the
other hand didn't pointlessly renumber things. So we'd need to find a
way to define the ordinals in libc/sysv/syscalls.sh twice for Linux. The
same goes for other ISAs too. Especially MIPS. For the Linux Kernel
alone, syscall magic numbers and data structure layouts are totally
different, and that's likely the case for other ISAs on other operating
systems too. Probably because ISA code historically got contributed to
open source by the companies that made the chips. Ulrich Drepper wrote
an amusing essay on the subject some years back.
We're now scrubbing environment variables in compile.com since gnu make
was not behaving as expected. It also appears there was a regression in
recent revisions that caused ASAN to be turned off for most binaries in
dbg mode, which has now been fixed. Cosmopolitan is fully ASAN hardened
down to the lowest level libraries and it doesn't need any interceptors
- Reduce full build latency from ~20s to ~18s
- Bring back silent mode if `make V=0` is passed
- Demodernize utimes() polyfill so it works RHEL5
- Delete some old shell scripts that are no longer needed
- Truncate long lines when outputting builds to Emacs buffers
You can now build Cosmopolitan with Clang:
make -j8 MODE=llvm
o/llvm/examples/hello.com
The assembler and linker code is now friendly to LLVM too.
So it's not needed to configure Clang to use binutils under
the hood. If you love LLVM then you can now use pure LLVM.
It turns out adding OpenBSD msyscall() origin verification broke the
--ftrace flag. The executable needs to issue raw syscalls while it's
rewriting itself. So they need to be in the same section, and that's
just plain simpler too.
Compilers like GCC require comments on lines like `#endif rdmsr`. Since
the rdmsr macro was only being used in arch_prctl(), I've localized the
macro, and I'm considering deleting arch_prctl() too, since there isn't
any way to have mem segments unfortunately across operating systems ;_;
The remaining changed lines are due to clang-format which runs on auto.
You can now use cosmopolitan.h with an ANSI C89 compiler like MSVC. The
Cosmopolitan codebase itself won't support being compiled that way. But
you can build objects that link against Cosmopolitan using any compiler
and you can furthermore use tools like IntelliSense that can't even GNU
See also #40
- Get ASAN working on Windows.
- Deleting directories and then recreating them with the same name in a
short period of time appears to be a no-no on Windows.
- There's no reason to call FlushFileBuffers on close() for pipes, and
it's harmful since it might block indefinitely for no good reason.
- Support deterministic stacks on OpenBSD
- Support OpenBSD system call origin verification
- Fix overrun by one in chibicc string token allocator
- Get all chibicc tests passing under Address Sanitizer
We now have an integration test that runs the amalgamated sources
through a C++ compiler, to prevent the recurrence of such issues.
Fixes#38
Thanks @gbbnfhb for the report!
This change enables Address Sanitizer systemically w/ `make MODE=dbg`.
Our version of Rust's `unsafe` keyword is named `noasan` which is used
for two functions that do aligned memory chunking, like `strcpy.c` and
we need to fix the tiny DEFLATE code, but that's it everything else is
fabulous you can have all the fischer price security blankets you need
Best of all is we're now able to use the ASAN data in Blinkenlights to
colorize the memory dumps. See the screenshot below of a test program:
https://justine.lol/blinkenlights/asan.png
Which is operating on float arrays stored on the stack, with red areas
indicating poisoned memory, and the green areas indicate valid memory.
The libm code from musl wasn't being used since most of these functions
are implemented using x87 which goes faster than a library intended for
risc machines.
We always favor calling functions like openat(), fstatat(), etc. because
Linux, XNU, FreeBSD, and OpenBSD all elected to support them, while some
systems like Android love them so much, that they stopped supporting the
old interfaces.
This change ensures that when dirfd is actually a dirfd and not AT_FDCWD
we'll do the right thing on Windows NT. We use an API that's been around
since Vista to accomplish that.
This change also adds exponential backoff to chdir() on Windows since it
seems almost as flaky on Windows 7 as the rmdir() function.
Justine says nay for the time being. Only XNU implements this. It's not
clear what ABI XNU is using but it's obviously not the one in the POSIX
documentation link below. Since all platforms implement vfork, it might
be better to empirically gauge the intersection of consensus which will
have better performance than this interface.
https://pubs.opengroup.org/onlinepubs/009696699/xrat/xsh_chap03.html
