# Zcu: convert Decl.zir_inst_index to a TrackedInst.Index.Optional · gitcafe/zig

[View on GitCafe](https://git.cafe/gitcafe/zig/commit/d4ce1ec8dd2bb63bafda7e6fe23315d167492a1b)

Repository: [gitcafe/zig](https://git.cafe/gitcafe/zig)

Visibility: public

Requested revision: d4ce1ec8dd2bb63bafda7e6fe23315d167492a1b

Requested commit: d4ce1ec8dd2bb63bafda7e6fe23315d167492a1b

Commit: d4ce1ec8dd2bb63bafda7e6fe23315d167492a1b

Tree: f3365c9dbf569b12c61e1ad301621945db5d849c

Author: mlugg

Committer: mlugg

## Message

```
Zcu: convert Decl.zir_inst_index to a TrackedInst.Index.Optional

This makes tracking easier across incremental updates: `scanDecl` can
now tell whether an existing decl in a namespace was mapped to the one
it's analyzing in the new ZIR.

```

## Parents

- [7c4793f23c971f5305c63f1b343e7f8576f32781](https://git.cafe/gitcafe/zig/commit/7c4793f23c971f5305c63f1b343e7f8576f32781?format=markdown)

[Source at this commit](https://git.cafe/gitcafe/zig/tree/d4ce1ec8dd2bb63bafda7e6fe23315d167492a1b?format=markdown)