fix: MIR evaluation of sized &T with recursive const fn#22030
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ChayimFriedman2 merged 1 commit intorust-lang:masterfrom Apr 13, 2026
Merged
fix: MIR evaluation of sized &T with recursive const fn#22030ChayimFriedman2 merged 1 commit intorust-lang:masterfrom
ChayimFriedman2 merged 1 commit intorust-lang:masterfrom
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Previously, we didn't recurse in Evaluator::create_memory_map() or Evaluator::patch_addresses() when handling references with a known size. This caused problems for hover rendering on const values, which would build a memory map for evaluated allocations and then pretty-printed values by following references through that map. As a result, references in the map still pointed to the original addresses, meaning that the value pretty-printer would see the type parameters before substitution. This could cause stack overflows on well-formed Rust code using recursive const functions. Add a regression test for hovering on a recursive const fn that previously caused stack overflow. Fixes rust-lang#21503 AI disclosure: I used Codex with GPT 5.4 to investigate the issue and write the initial version of this commit.
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Previously, we didn't recurse in Evaluator::create_memory_map() or Evaluator::patch_addresses() when handling references with a known size.
This caused problems for hover rendering on const values, which would build a memory map for evaluated allocations and then pretty-printed values by following references through that map.
As a result, references in the map still pointed to the original addresses, meaning that the value pretty-printer would see the type parameters before substitution. This could cause stack overflows on well-formed Rust code using recursive const functions.
Add a regression test for hovering on a recursive const fn that previously caused stack overflow.
Fixes #21503
AI disclosure: I used Codex with GPT 5.4 to investigate the issue and write the initial version of this commit.