fix issue 19755 - Compiler crash

[ghost]

Just an easy to fix unsafe access

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	19755	normal	Compiler crash

Testing this PR locally

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

dub fetch digger
dub run digger -- build "stable + dmd#9470"

[ghost]

@thewilsonator, sorry I had to force push, auto-merge label needed again.

[thewilsonator]

Done.

[UplinkCoder]

There seems to be another bug here.
Thunk self should NOT be rewritten to Thunk!int self

[UplinkCoder]

ping @thewilsonator

[thewilsonator]

Hmm, yeah. That should error on use of uninstantiated template.

[ghost]

You mean that it's a hdrgen bug or a semantic one ?

[UplinkCoder]

not sure; I assume it's sema.