Storing defers this way has the benefits that the defer doesn't get
analyzed multiple times in AstGen, it takes up less space, and it
makes Sema aware of defers allowing for 'unreachable else prong'
error on error sets in generic code.
The disadvantage is that it is a bit more complex and errdefers with
payloads now emit a placeholder instruction (but those are rare).
Sema.zig before:
Total ZIR bytes: 3.7794370651245117MiB
Instructions: 238996 (2.051319122314453MiB)
String Table Bytes: 89.2802734375KiB
Extra Data Items: 430144 (1.640869140625MiB)
Sema.zig after:
Total ZIR bytes: 3.3344192504882812MiB
Instructions: 211829 (1.8181428909301758MiB)
String Table Bytes: 89.2802734375KiB
Extra Data Items: 374611 (1.4290275573730469MiB)
Macro definitions are simply a slice of bytes, which may not be
UTF-8 encoded. If they are not UTF-8 encoded, escape non-printable
and non-ASCII characters as `\xNN`.
Fixes#12784
This is a temporary workaround to an unclear platform-dependence
behavior we have in libstd for `std.fs.File` abstraction. See
https://github.com/ziglang/zig/issues/12783 for more information.
Previously if a decl failed its capture scope would be deallocated and
set to undefined which would then lead to invalid dereference in
`zirClosureGet`. To avoid this set the capture scope to a special
failed state and fail the current decl with dependency failure if
the failed state is encountered in `zirClosureGet`.
Closes#12433Closes#12530Closes#12593
Extern functions were missing attributes such as "readonly" on
non-optional pointers, and "byval" which is required to match C ABI.
Follow-up from bf28765a975355c27558eaa86cf00ccb29b663a7.
closes#12683
This is problematic because in practice it depends on whether the
compiler backend supports it too, as evidenced by the TODO comment about
LLVM not supporting some architectures that in fact do support tail
calls.
Instead this logic is organized strategically in src/target.zig, part of
the internal compiler source code, and the behavior tests in question
duplicate some logic for deciding whether to proceed with the test.
The proper place to expose this flag is in `@import("builtin")` - the
generated source file - so that third party compilers can advertise
whether they support tail calls.
