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.
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
The cosmo_dlsym() function now returns the raw function address. You
need to call cosmo_dltramp() on the result, to make it safe to call.
This change is important, because cosmo_dltramp() magic can't always
work; for some tricky functions, you need to translate ABIs by hand.
If cosmo_dlopen() is linked on AMD64 then the runtime will switch to
using %gs for thread-local storage. This eliminates the need for the
imported symbol trampoline. It's now safer to pass function pointers
back and forth with imported libraries. Your program gets recompiled
at runtime to make it happen and the overhead is a few milliseconds.
Our dynamic linking implementation is now able to support functions with
dozens of parameters. In addition to having extra integral arguments you
can now pass vector registers using intrinsic types. Lastly, you can now
return multiple values, which is useful for functions returning structs.
At least in neovim, `│vi:` is not recognized as a modeline because it
has no preceding whitespace. After fixing this, opening a file yields
an error because `net` is not an option. (`noet`, however, is.)
- Introduce MAP_JIT which is zero on other platforms
- Invent __jit_begin() and __jit_end() which wrap Apple's APIs
- Runtime dispatch to sys_icache_invalidate() in __clear_cache()
- Use good ELF technique in cosmo_dlopen()
- Make strerror() conform more to other libc impls
- Introduce __clear_cache() and use it in cosmo_dlopen()
- Remove libc/fmt/fmt.h header (trying to kill off LIBC_FMT)
After hearing horror stories from a trusted colleague, I don't think
this is the kind of API we want to be supporting. Also SQLite wisdom
regarding fdatasync() has been added to the documentation.
Imported functions are now aspected with a trampoline that blocks
signals and changes the thread-local storage register. This means
bigger more complicated libraries can now be imported even though
the whole technique remains fundamentally unsafe.
Every program built using Cosmopolitan is statically-linked. However
there are some cases, e.g. GUIs and video drivers, where linking the
host platform libraries is desirable. So what we do in such cases is
launch a stub executable using the host platform's libc, and longjmp
back into this executable. The stub executable passes back to us the
platform-specific dlopen() implementation, which we shall then wrap.
Here's the list of platforms that are supported so far:
- x86-64 Linux w/ Glibc
- x86-64 Linux w/ Musl Libc
- x86-64 FreeBSD
- x86-64 Windows
- aarch64 Linux w/ Glibc
- aarch64 MacOS
What this means is your Cosmo programs can call foreign functions on
your host operating system. However, it's important to note that any
foreign library you link won't have the ability to call functions in
your Cosmopolitan program. For example it's now technically possible
that Lua can load a module, however that almost certainly won't work
since the Lua module won't have access to Cosmo's Lua API.
Kudos to @jacereda for figuring out how to do this.
