* std.Mutex API is improved to not have init() deinit(). This API is
designed to support static initialization and does not require any
resource cleanup. This also happens to work around some kind of
stage1 behavior that wasn't letting the new allocator mutex code
get compiled.
* the general purpose allocator now returns a bool from deinit()
which tells if there were any leaks. This value is used by the test
runner to fail the tests if there are any.
* self-hosted compiler is updated to use the general purpose allocator
when not linking against libc.
`std.GeneralPurposeAllocator` is now available. It is a function that
takes a configuration struct (with default field values) and returns an
allocator. There is a detailed description of this allocator in the
doc comments at the top of the new file.
The main feature of this allocator is that it is *safe*. It
prevents double-free, use-after-free, and detects leaks.
Some deprecation compile errors are removed.
The Allocator interface gains `old_align` as a new parameter to
`resizeFn`. This is useful to quickly look up allocations.
`std.heap.page_allocator` is improved to use mmap address hints to avoid
obtaining the same virtual address pages when unmapping and mapping
pages. The new general purpose allocator uses the page allocator as its
backing allocator by default.
`std.testing.allocator` is replaced with usage of this new allocator,
which does leak checking, and so the LeakCheckAllocator is retired.
stage1 is improved so that the `@typeInfo` of a pointer has a lazy value
for the alignment of the child type, to avoid false dependency loops
when dealing with pointers to async function frames.
The `std.mem.Allocator` interface is refactored to be in its own file.
`std.Mutex` now exposes the dummy mutex with `std.Mutex.Dummy`.
This allocator is great for debug mode, however it needs some work to
have better performance in release modes. The next step will be setting
up a series of tests in ziglang/gotta-go-fast and then making
improvements to the implementation.
* breaking changes to the API. Some of the weird decisions from before
are changed to what would be more expected.
- `get` returns `?V`, use `getEntry` for the old API.
- `put` returns `!void`, use `fetchPut` for the old API.
* HashMap now has a comptime parameter of whether to store hashes with
entries. AutoHashMap has heuristics on whether to set this parameter.
For example, for integers, it is false, since equality checking is
cheap, but for strings, it is true, since equality checking is
probably expensive.
* The implementation has a separate array for entry_index /
distance_from_start_index. Entries no longer has holes; it is an
ArrayList, and iteration is simpler and more cache coherent.
This is inspired by Python's new dictionaries.
* HashMap is separated into an "unmanaged" and a "managed" API. The
unmanaged API is where the actual implementation is; the managed API
wraps it and provides a more convenient API, storing the allocator.
* Memory usage: When there are less than or equal to 8 entries, HashMap
now incurs only a single pointer-size integer as overhead, opposed to
using an ArrayList.
* Since the entries array is separate from the indexes array, the holes
in the indexes array take up less room than the holes in the entries
array otherwise would. However the entries array also allocates
additional capacity for appending into the array.
* HashMap now maintains insertion order. Deletion performs a "swap
remove". It's now possible to modify the HashMap while iterating.
- stderr_file_writer was unused
- stderr_stream was a pointer to a stream, rather than a stream
- other functions assumed that getStderrStream has already been called
Start implementing https://github.com/ziglang/zig/issues/4917 which is to rename instream/outstream to reader/writer. This first change allows code to use Writer/writer instead of OutStream/outStream, but still maintains the old outstream names with "Deprecated" comments.
The main goal here is to make the function pointers comptime, so that we
don't have to do the crazy stuff with async function frames.
Since InStream, OutStream, and SeekableStream are already generic
across error sets, it's not really worse to make them generic across the
vtable as well.
See #764 for the open issue acknowledging that using generics for these
abstractions is a design flaw.
See #130 for the efforts to make these abstractions non-generic.
This commit also changes the OutStream API so that `write` returns
number of bytes written, and `writeAll` is the one that loops until the
whole buffer is written.
* re-introduce `std.build.Target` which is distinct from `std.Target`.
`std.build.Target` wraps `std.Target` so that it can be annotated as
"the native target" or an explicitly specified target.
* `std.Target.Os` is moved to `std.Target.Os.Tag`. The former is now a
struct which has the tag as well as version range information.
* `std.elf` gains some more ELF header constants.
* `std.Target.parse` gains the ability to parse operating system
version ranges as well as glibc version.
* Added `std.Target.isGnuLibC()`.
* self-hosted dynamic linker detection and glibc version detection.
This also adds the improved logic using `/usr/bin/env` rather than
invoking the system C compiler to find the dynamic linker when zig
is statically linked. Related: #2084
Note: this `/usr/bin/env` code is work-in-progress.
* `-target-glibc` CLI option is removed in favor of the new `-target`
syntax. Example: `-target x86_64-linux-gnu.2.27`
closes#1907
