This was regressed in d657b6c0e2ab7c47f5416dc4df1abb2bfbecd4b6, when
the comptime memory model for unions was changed to allow them to have
no defined tag type.
This change allows struct field inits to use layout information
of their own struct without causing a circular dependency.
`semaStructFields` caches the ranges of the init bodies in the `StructType`
trailing data. The init bodies are then resolved by `resolveStructFieldInits`,
which is called before the inits are actually required.
Within the init bodies, the struct decl's instruction is repurposed to refer
to the field type itself. This is to allow us to easily rebuild the inst_map
mapping required for the init body instructions to refer to the field type.
Thanks to @mlugg for the guidance on this one!
The logic in 509be7cf1f10c5d329d2b0524f2af6bfcabd52de assumed that
`use_llvm` meant that the LLVM backend would be used, however, use_llvm
is false when there are no zig files to compile, which is the case for
zig cc. This logic resulted in `-fsingle-threaded` which made libc++
fail to compile for C++ code that includes the threading abstractions
(such as LLVM).
Perform these transformations in this priority order:
1. If the `else` expression is missing or an empty block, replace the condition with `if (true)` if it is not already.
2. If the `then` block is empty, replace the condition with `if (false)` if it is not already.
3. If the condition is `if (true)`, replace the `if` expression with the contents of the `then` expression.
4. If the condition is `if (false)`, replace the `if` expression with the contents of the `else` expression.
Changes:
- Add `isMangledIdent` to determine if `fmtIdent` would make any edits to the identifier
- Any function that has a mangled identifier is referred to using the mangled identifer
within the current file, but if it is exported the first export will be with the non-mangled name.
- Add `zig_import` to import a symbol under a different name
- Add a level of indirection to float function names. Now, they are referred to as
`zig_float_fn_<float type>_<operation>`. The definitions in zig.h are wrapped
with `zig_import` to import the symbol under the real name.
The specific problem that sparked this change was the combination of
`zig_libc_name_f80(name) __##name##x` with the input `fma`, resulting
in `__fmax`, which is a new intrinsic in recent versions of cl.exe.
With the above changes in place, compiler_rt can output the following:
```
static zig_weak_linkage_fn zig_f80 zig_e___fmax(zig_f80, zig_f80, zig_f80);
zig_export(zig_weak_linkage_fn zig_f80 zig_e___fmax(zig_f80, zig_f80, zig_f80), __fmax, "__fmax");
```
Within compiler_rt, `zig_e___fmax` is used to refer to the function, but consumers
will import `__fmax`, which maps to their `zig_float_fn_f80_fma` definition from zig.h.
Server networking application typically accept multiple connections. Multishot
accept simplifies handling these situations. Applications submits once and
receives CQE whenever a new connection request comes in.
Multishot is active until it is canceled or experience error. While active, and
further notification are expected CQE completion will have IORING_CQE_F_MORE set
in the flags. If this flag isn't set, the application must re-arm this request
by submitting a new one.
Reference: [io_uring and networking in 2023](https://github.com/axboe/liburing/wiki/io_uring-and-networking-in-2023#multi-shot)
* don't reset the rng. it seems like it was getting stuck trying the
same transforms over and over again.
* slide the window over after failing a large transform set, idea being
that transformations in the failed set are more likely to be
problematic.
and use that to fix up usused variable declarations and parameters that
are caused by transformations.
also add a transformation to replace global variable init with
`undefined`.
