Fix Issue 15525 - SEGV running semantic analysis on non-root decl tha…

[RazvanN7]

…t has errors

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	15525	critical	SEGV running semantic analysis on non-root decl that has errors.

⚠️⚠️⚠️ Warnings ⚠️⚠️⚠️

• Regression or critical bug fixes should always target the stable branch. Learn more about rebasing to stable or the D release process.

To target stable perform these two steps:

1. Rebase your branch to upstream/stable:

git rebase --onto upstream/stable upstream/master

2. Change the base branch of your PR to stable

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#14359"