* `comptime const` is redundant
* don't use `extern enum`; specify a tag type.
`extern enum` is only when you need tags to alias. But aliasing tags
is a smell. I will be making a proposal shortly to remove `extern enum`
from the language.
* there is no such thing as `packed enum`.
* instead of `catch |_|`, omit the capture entirely.
* unused function definition with missing parameter name
* using `try` outside of a function or test
Primarily this required fixing `setCondBrPayloadElideBlockStorePtr` to
not assume there would always be two `store_to_block_ptr` instructions
in each of the condbr prongs.
This commit also reclaims +2 ZIR instruction tags by moving the
following to `extended`:
* func_var_args
* func_extra
* func_extra_var_args
The following ZIR instruction tag is added:
* func_inferred
I've run into this footgun enough times, nearly every time I want
`ensureUnusedCapacity`, not `ensureCapacity`. This commit deprecates
`ensureCapacity` in favor of `ensureTotalCapacity` and introduces
`ensureUnusedCapacity`.
* AstGen: represent compile errors in ZIR rather than returning
`error.AnalysisFail`.
* ZIR: remove decl_ref and decl_val instructions. These are replaced by
`decl_ref_named` and `decl_val_named`, respectively, which will
probably get renamed in the future to the instructions that were just
deleted.
* AstGen: implement `@This()`, `@fence()`, `@returnAddress()`, and
`@src()`.
* AstGen: struct_decl improved to support fields_len=0 but have decls.
* AstGen: fix missing null bytes after compile error messages.
* SrcLoc: no longer depend on `Decl`. Instead have an explicit field
`parent_decl_node` which is an absolute AST Node index.
* Module: `failed_files` table can have null value, in which case the
key, which is a `*Scope.File`, will have ZIR errors in it.
* ZIR: implement text rendering of struct decls.
* CLI: introduce debug_usage and `zig astgen` command which is enabled
when the compiler is built in debug mode.
