This is a breaking change. Before, usage looked like this:
```zig
const held = mutex.acquire();
defer held.release();
```
Now it looks like this:
```zig
mutex.lock();
defer mutex.unlock();
```
The `Held` type was an idea to make mutexes slightly safer by making it
more difficult to forget to release an aquired lock. However, this
ultimately caused more problems than it solved, when any data structures
needed to store a held mutex. Simplify everything by reducing the API
down to the primitives: lock() and unlock().
Closes#8051Closes#8246Closes#10105
The main purpose of this branch is to explore avoiding the
`usingnamespace` feature of the zig language, specifically with regards
to `std.os` and related functionality.
If this experiment is successful, it will provide a data point on
whether or not it would be practical to entirely remove `usingnamespace`
from the language.
In this commit, `usingnamespace` has been completely eliminated from
the Linux x86_64 compilation path, aside from io_uring.
The behavior tests pass, however that's as far as this branch goes. It is
very breaking, and a lot more work is needed before it could be
considered mergeable. I wanted to put a pull requset up early so that
zig programmers have time to provide feedback.
This is progress towards closing #6600 since it clarifies where the
actual "owner" of each declaration is, and reduces the number of
different ways to import the same declarations.
One of the main organizational strategies used here is to do namespacing
with real namespaces (e.g. structs) rather than by having declarations
share a common prefix (the C strategy). It's no coincidence that
`usingnamespace` has similar semantics to `#include` and becomes much
less necessary when using proper namespaces.
We already have a LICENSE file that covers the Zig Standard Library. We
no longer need to remind everyone that the license is MIT in every single
file.
Previously this was introduced to clarify the situation for a fork of
Zig that made Zig's LICENSE file harder to find, and replaced it with
their own license that required annual payments to their company.
However that fork now appears to be dead. So there is no need to
reinforce the copyright notice in every single file.
On arm64 macOS, the address of the last frame is 0x0 rather than
a positive value like 0x1 on x86_64 macOS, therefore, we overflow
an integer trying to subtract 1 when printing the stack trace. This
patch fixes it by first checking for this condition before trying
to subtract 1.
Note that we do not need to signal the `SignalIterator` about this
as it will correctly detect this condition on the subsequent iteration
and return `null`, thus terminating the loop.
No functional changes are expected, this patch is only moving some code
in order to slim the huge bowl of spaghetti that is debug.zig.
The amount of memory leaked on error is much less than before but not
zero, some further work is required to smooth the edges of this old part
of the stdlib.
Conflicts:
* build.zig
* src/Compilation.zig
* src/codegen/spirv/spec.zig
* src/link/SpirV.zig
* test/stage2/darwin.zig
- this one might be problematic; start.zig looks for `main` in the
root source file, not `_main`. Not sure why there is an underscore
there in master branch.
Use .bold instead of .white, the effect is the same for light-on-dark
terminals but greatly improves the readability for dark-on-light ones.
Closes#8761
Flush all the register windows to stack before starting the stack walk,
we may otherwise try to read garbage and crash and burn.
Add a few comptime annotations to debloat some functions.
This temporary patch fixes a segfault caused by miscompilation
by the LLD when generating stubs for initialization of thread local
storage. We effectively bypass TLS in the default panic handler
so that no segfault is generated and the stack trace is correctly
reported back to the user.
Note that, this is linked directly to a bigger issue with LLD
ziglang/zig#7527 and when resolved, we only need to remove the
`comptime` code path introduced with this patch to use the default
panic handler that relies on TLS.
Co-authored-by: Andrew Kelley <andrew@ziglang.org>
* move concurrency primitives that always operate on kernel threads to
the std.Thread namespace
* remove std.SpinLock. Nobody should use this in a non-freestanding
environment; the other primitives are always preferable. In
freestanding, it will be necessary to put custom spin logic in there,
so there are no use cases for a std lib version.
* move some std lib files to the top level fields convention
* add std.Thread.spinLoopHint
* add std.Thread.Condition
* add std.Thread.Semaphore
* new implementation of std.Thread.Mutex for Windows and non-pthreads Linux
* add std.Thread.RwLock
Implementations provided by @kprotty
* split std.ResetEvent into:
- ResetEvent - requires init() at runtime and it can fail. Also
requires deinit().
- StaticResetEvent - can be statically initialized and requires no
deinitialization. Initialization cannot fail.
* the POSIX sem_t implementation can in fact fail on initialization
because it is allowed to be implemented as a file descriptor.
* Completely define, clarify, and explain in detail the semantics of
these APIs. Remove the `isSet` function.
* `ResetEvent.timedWait` returns an enum instead of a possible error.
* `ResetEvent.init` takes a pointer to the ResetEvent instead of
returning a copy.
* On Darwin, `ResetEvent` is implemented using Grand Central Dispatch,
which is exposed by libSystem.
stage2 changes:
* ThreadPool: use a single, pre-initialized `ResetEvent` per worker.
* WaitGroup: now requires init() and deinit() and init() can fail.
- Add a `reset` function.
- Compilation initializes one for the work queue in creation and
re-uses it for every update.
- Rename `stop` to `finish`.
- Simplify the implementation based on the usage pattern.
stderr_mutex may still be held when we reach the signal handler, grab
our own stderr handle to print the error messages and avoid deadlocking.
Closes#7247
