This change adds to Liveness a simple pattern match for the
try-like `.condbr` blocks emitted by Sema's safety checks. This
allows us to determine that these do not modify memory, which
permits us to elide additional loads in the backend.
As @Vexu points out in the main issue, this is probably not a
complete solution on its own. We'll still want a way to reliably
narrow the load/copy when performing several consecutive accesses,
such as `foo.arr[x][y].z`
Resolves https://github.com/ziglang/zig/issues/12215
This helps prevent errors related to undefined pointers being passed
through to some OS apis when slices have 0 length.
Tests have also been added to catch these cases.
Split the original `defer.zig` doctest into 3 doctest:
1. Document the defer keyword
2. Document that the return statement is not allowed inside a defer
expression
3. Document the errdefer keyword
Replace "method" with "expression" in the text `defer method`.
The PCG32 fill function seems to have been copy-pasted from code using u64, so requesting `n` bytes where `(n & 7) > 4` bytes would cause the last few bytes to be all 0.
This fixes a class of bugs on macOS where a segfault happening in
a loaded dylib with no debug info would cause a panic in the panic
handler instead of simply noting that the dylib has no valid debug
info via `error.MissingDebugInfo`. An example could be code linking
some system dylib and causing some routine to segfault on say invalid
pointer value, which should normally cause Zig to print an incomplete
stack trace anchored at the currently loaded image and backtrace all
the way back to the Zig binary with valid debug info. Currently, in
a situation like this we would trigger a panic within a panic.
This includes the latest changes from master branch with fixes to the C
backend that affect aarch64-windows which are necessary to build from
source on this target.
This allows using `zig ar` for `CMAKE_AR`. Unfortunately, it requires a
patch to CMakeLists.txt and cannot be done merely with flags to the
cmake line.
We definitely want a shared lock on a cache hit. Without this, we get a
deadlock when Zig is asked to compile the same C source file multiple
times as part of the same compilation.
This is a partial revert of 8ccb9a6ad327a4d7fbc321b33d4aa66a27a1f5ee.
cc @kcbanner
These bugs were triggered in the C backend by aarch64-specific code in
os/windows.zig. Intentionally not updating zig1.wasm yet because of
upcoming changes and since aarch64-windows is not tested on master yet.
