Now that allocator.resize() is allowed to fail, programs may wish to
test code paths that handle resize() failure. The simplest way to do
this now is to replace the vtable of the testing allocator with one
that uses Allocator.noResize for the 'resize' function pointer.
An alternative way to support this testing capability is to augment the
FailingAllocator (which is already useful for testing allocation failure
scenarios) to intentionally fail on calls to resize(). To do this, add a
'resize_fail_index' parameter to the FailingAllocator that causes
resize() to fail after the given number of calls.
The 'at least' behavior of the Allocator interface was removed in #13666, so anything that used reallocAtLeast or the .at_least Exact behavior could still have doc comments that reference no-longer-true behavior.
Funnily enough, ArrayList is the only place that used this functionality (outside of allocator test cases), so its doc comments are the only things that need to be fixed. This was checked by resetting to deda6b5146 and searching for all instances of `reallocAtLeast` and `.at_least` (one of which would need to be used to get the `.at_least` behavior)
Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:
* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
The previous commit introduced an optimization to the LLVM backend that
makes `@memset` lower more optimally when the element is comptime-known
and has a repeating byte pattern.
By making these functions inline, if the element parameter is
comptime-known at the callsite, it will be comptime-known in the
`@memset` call, causing more use of the LLVM `memset` intrinsic rather
than an inline for loop when using the LLVM backend.
This affects, for example, std.crypto.argon2, which calls
appendNTimesAssumeCapacity with a `[128]u64` as the element. This is now
lowered with a single `memset` call.
Now they use slices or array pointers with any element type instead of
requiring byte pointers.
This is a breaking enhancement to the language.
The safety check for overlapping pointers will be implemented in a
future commit.
closes#14040
* docs(std.math): elaborate on difference between absCast and absInt
* docs(std.rand.Random.weightedIndex): elaborate on likelihood
I think this makes it easier to understand.
* langref: add small reminder
* docs(std.fs.path.extension): brevity
* docs(std.bit_set.StaticBitSet): mention the specific types
* std.debug.TTY: explain what purpose this struct serves
This should also make it clearer that this struct is not supposed to provide unrelated terminal manipulation functionality such as setting the cursor position or something because terminals are complicated and we should keep this struct simple and focused on debugging.
* langref(package listing): brevity
* langref: explain what exactly `threadlocal` causes to happen
* std.array_list: link between swapRemove and orderedRemove
Maybe this can serve as a TLDR and make it easier to decide.
* PrefetchOptions.locality: clarify docs that this is a range
This confused me previously and I thought I can only use either 0 or 3.
* fix typos and more
* std.builtin.CallingConvention: document some CCs
* langref: explain possibly cryptic names
I think it helps knowing what exactly these acronyms (@clz and @ctz) and
abbreviations (@popCount) mean.
* variadic function error: add missing preposition
* std.fmt.format docs: nicely hyphenate
* help menu: say what to optimize for
I think this is slightly more specific than just calling it
"optimizations". These are speed optimizations. I used the word
"performance" here.
#13666 introduced a footgun when using `toOwnedSlice` with `errdefer array_list.deinit()`, since `toOwnedSlice` could retain capacity if `resize` failed, meaning it would leak without `deinit` being called. This meant that the only correct way to use `toOwnedSlice` was with `defer` instead of `errdefer` to ensure that the ArrayList would get cleaned up.
Now, toOwnedSlice will now behave similarly to how it did before #13666, in that it will always clear the ArrayList's capacity if the resize/realloc succeeds.
This also reverts commit 05890a12f5, which was contingent on the modified toOwnedSlice behavior.
Closes#13946
While it is already mentioned on the `items` attributes of the structs, it is
interesting to comment in every method potentially invalidating pointers to items
that they may do so.
`ArrayList.ensureTotalCapacityPrecise` uses `Allocator.reallocAtLeast` under
the hood, which can return more than `new_capacity` bytes if `alignment
!= @alignOf(T)`. This implementation of `clone` assures that
the case of `ensureTotalCapacityPrecise` is handled correctly.
Thanks @Vexu and @squeek502 for pointing this out.
initCapacity did and still does use the ensureTotalCapacityPrecise logic because the initial capacity of an ArrayList is not important in terms of how it grows, so allocating a more exact slice up-front allows for saving memory when the array list never exceeds that initial allocation size. There are use cases where this precise capacity is useful outside of the `init` function, though, like in instances where the user does not call the `init` function themselves but otherwise knows that an ArrayList is empty so calling `ensureTotalCapacityPrecise` can give the same memory savings that `initCapacity` would have.
Closes#9775
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.
Conflicts:
* doc/langref.html.in
* lib/std/enums.zig
* lib/std/fmt.zig
* lib/std/hash/auto_hash.zig
* lib/std/math.zig
* lib/std/mem.zig
* lib/std/meta.zig
* test/behavior/alignof.zig
* test/behavior/bitcast.zig
* test/behavior/bugs/1421.zig
* test/behavior/cast.zig
* test/behavior/ptrcast.zig
* test/behavior/type_info.zig
* test/behavior/vector.zig
Master branch added `try` to a bunch of testing function calls, and some
lines also had changed how to refer to the native architecture and other
`@import("builtin")` stuff.
