preparing to rearrange std.io namespace into an interface
how to upgrade:
std.io.getStdIn() -> std.fs.File.stdin()
std.io.getStdOut() -> std.fs.File.stdout()
std.io.getStdErr() -> std.fs.File.stderr()
`castTruncatedData` was a poorly worded error (all shrinking casts
"truncate bits", it's just that we assume those bits to be zext/sext of
the other bits!), and `negativeToUnsigned` was a pointless distinction
which forced the compiler to emit worse code (since two separate safety
checks were required for casting e.g. 'i32' to 'u16') and wasn't even
implemented correctly. This commit combines those safety panics into one
function, `integerOutOfBounds`. The name maybe isn't perfect, but that's
not hugely important; what matters is the new default message, which is
clearer than the old ones: "integer does not fit in destination type".
Pointers to thread-local variables do not have their addresses known
until runtime, so it is nonsensical for them to be comptime-known. There
was logic in the compiler which was essentially attempting to treat them
as not being comptime-known despite the pointer being an interned value.
This was a bit of a mess, the check was frequent enough to actually show
up in compiler profiles, and it was very awkward for backends to deal
with, because they had to grapple with the fact that a "constant" they
were lowering might actually require runtime operations.
So, instead, do not consider these pointers to be comptime-known in
*any* way. Never intern such a pointer; instead, when the address of a
threadlocal is taken, emit an AIR instruction which computes the pointer
at runtime. This avoids lots of special handling for TLVs across
basically all codegen backends; of all somewhat-functional backends, the
only one which wasn't improved by this change was the LLVM backend,
because LLVM pretends this complexity around threadlocals doesn't exist.
This change simplifies Sema and codegen, avoids a potential source of
bugs, and potentially improves Sema performance very slightly by
avoiding a non-trivial check on a hot path.
Nothing interesting here; literally just the bare minimum so I can work on this
on and off in a branch without worrying about merge conflicts in the non-backend
code.
* ucontext_t ptr is 8-byte aligned instead of 16-byte aligned which @alignCast() expects
* Retrieve pc address from ucontext_t since unwind_state is null
* Work around __mcontext_data being written incorrectly by the kernel
By returning an initialized sigset (instead of taking the set as an output
parameter), these functions can be used to directly initialize the `mask`
parameter of a `Sigaction` instance.
When linking a libc, Zig should defer to the C library for sigset
operations. The pre-filled constants signal sets (empty_sigset,
filled_sigset) are not compatible with C library initialization, so remove
them and use the runtime `sigemptyset` and `sigfillset` methods to
initialize any sigset.
Emscripten currently implements `emscripten_return_address()` by calling
out into JavaScript and parsing a stack trace, which introduces
significant overhead that we would prefer to avoid in release builds.
This is especially problematic for allocators because the generic parts
of `std.mem.Allocator` make frequent use of `@returnAddress`, even
though very few allocator implementations even observe the return
address, which makes allocators nigh unusable for performance-critical
applications like games if the compiler is unable to devirtualize the
allocator calls.
Functions like isMinGW() and isGnuLibC() have a good reason to exist: They look
at multiple components of the target. But functions like isWasm(), isDarwin(),
isGnu(), etc only exist to save 4-8 characters. I don't think this is a good
enough reason to keep them, especially given that:
* It's not immediately obvious to a reader whether target.isDarwin() means the
same thing as target.os.tag.isDarwin() precisely because isMinGW() and similar
functions *do* look at multiple components.
* It's not clear where we would draw the line. The logical conclusion before
this commit would be to also wrap Arch.isX86(), Os.Tag.isSolarish(),
Abi.isOpenHarmony(), etc... this obviously quickly gets out of hand.
* It's nice to just have a single correct way of doing something.
* fix merge conflicts
* rename the declarations
* reword documentation
* extract FixedBufferAllocator to separate file
* take advantage of locals
* remove the assertion about max alignment in Allocator API, leaving it
Allocator implementation defined
* fix non-inline function call in start logic
The GeneralPurposeAllocator implementation is totally broken because it
uses global state but I didn't address that in this commit.
heap.zig: define new default page sizes
heap.zig: add min/max_page_size and their options
lib/std/c: add miscellaneous declarations
heap.zig: add pageSize() and its options
switch to new page sizes, especially in GPA/stdlib
mem.zig: remove page_size
- patch authored by Jacob Young
- tested on alpine-aarch64, 3.21.0, qemu-system 9.2.0
- issue manifested on Alpine Linux aarch64 under qemu-system where
zig2 fails during bootstrap: error.ProcessFdQuotaExceeded
* `std.builtin.Panic` -> `std.builtin.panic`, because it is a namespace.
* `root.Panic` -> `root.panic` for the same reason. There are type
checks so that we still allow the legacy `pub fn panic` strategy in
the 0.14.0 release.
* `std.debug.SimplePanic` -> `std.debug.simple_panic`, same reason.
* `std.debug.NoPanic` -> `std.debug.no_panic`, same reason.
* `std.debug.FormattedPanic` is now a function `std.debug.FullPanic`
which takes as input a `panicFn` and returns a namespace with all the
panic functions. This handles the incredibly common case of just
wanting to override how the message is printed, whilst keeping nice
formatted panics.
* Remove `std.builtin.panic.messages`; now, every safety panic has its
own function. This reduces binary bloat, as calls to these functions
no longer need to prepare any arguments (aside from the error return
trace).
* Remove some legacy declarations, since a zig1.wasm update has
happened. Most of these were related to the panic handler, but a quick
grep for "zig1" brought up a couple more results too.
Also, add some missing type checks to Sema.
Resolves: #22584
formatted -> full
When using the self-hosted backends, especially in incremental mode, the
.eh_frame_hdr section may be incomplete, so we can't treat it as authoritative.
Instead, if we started out intending to use .eh_frame_hdr but find that it's
incomplete, load .eh_frame/.debug_frame on demand and use that info going
forward.
This was done by regex substitution with `sed`. I then manually went
over the entire diff and fixed any incorrect changes.
This diff also changes a lot of `callconv(.C)` to `callconv(.c)`, since
my regex happened to also trigger here. I opted to leave these changes
in, since they *are* a correct migration, even if they're not the one I
was trying to do!
The freestanding and other OS targets by default need to just @trap in the
default Panic implementation.
And `isValidMemory` won't work with freestanding or other targets.
Update the unwind_freestanding.zig test case to also run on the 'other' OS
target, too. This should keep the Zig's stacktrace generation from
regressing on the standalone targets.
Xcode requires target arm64_32 (aarch64-watchos-ilp32) in order to
build code for Apple Watches. This commit fixes compilation errors
that appear when compiling with that target.
Introduces `std.builtin.Panic` which is a complete interface for
panicking. Provide `std.debug.FormattedPanic` and
`std.debug.SimplePanic` and let the user choose, or make their own.
Very simply add the format specifier to the print statement.
Since debug.print is hard coded I couldn't come up with a reasonalble
way to add a test, and since this function is simple enough I doubt it's
useful.
fixes one part of #21094
The compiler actually doesn't need any functional changes for this: Sema
does reification based on the tag indices of `std.builtin.Type` already!
So, no zig1.wasm update is necessary.
This change is necessary to disallow name clashes between fields and
decls on a type, which is a prerequisite of #9938.
