We were violating the POSIX standard which resulted in a deadlock on
musl v1.1.24 on aarch64 alpine linux, uncovered with the new ThreadPool
usage in the stage2 compiler.
std.os execv functions that accept an Allocator parameter are removed
because they are footguns. The POSIX standard does not allow calls to
malloc() between fork() and execv() and since it is common to both
(1) call execv() after fork() and (2) use std.heap.c_allocator,
Programmers are encouraged to go through the `std.process` API
instead, causing some dissonance when combined with `std.os` APIs.
I also slapped a big warning message on all the relevant doc comments.
* 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.
* Truncate user and group ids
Calls to `getuid`, `getgid` and their `eid` variants fail to compile on
64bit Linux systems because the return value of the syscall is of
`usize` and needs to be truncated to fit the size of `uid_t` that is 32
bit.
Thanks to @FireFox317 for figuring this out in Zig's Discord channel!
* Add a regression test for user and group ids
* Replace @truncate with @intCast
This should be safe because `uid_t` will be 32-bit.
* Add missing import for getauxval
* Add missing package names
* Revert "Add missing import for getauxval"
This reverts commit 38f93dc89e.
* Skip user and group test if builtin.link_libc
C compiler intrinsics can only appear as part of a function call. When called
they are implicitly cast to a function pointer; treat this as a non-null
pointer so that it emits as a regular Zig function call.
Put `pub usingnamespace @import("std").c.builtins;` at the top of translated
C files so that they will have access to builtin functions defined there.
Fixes#6707
We generally get away with atomic primitives, however a lock is required
around the refresh function since it traverses the Node graph, and we
need to be sure no references to Nodes remain after end() is called.
Everybody gets what they want!
* AT_RANDOM is completely ignored.
* On Linux, MADV_WIPEONFORK is used to provide fork safety.
* On pthread systems, `pthread_atfork` is used to provide fork safety.
* For systems that do not have the capability to provide fork safety,
the implementation falls back to calling getrandom() every time.
* If madvise is unavailable or returns an error, or pthread_atfork
fails for whatever reason, it falls back to calling getrandom() every
time.
* Applications may choose to opt-out of fork safety.
* Applications may choose to opt-in to unconditionally calling
getrandom() for every call to std.crypto.random.fillFn.
* Added `std.meta.globalOption`.
* Added `std.os.madvise` and related bits.
* Bumped up the size of the main thread TLS buffer. See the comment
there for justification.
* Simpler hot path in TLS initialization.
