Landing: 8ff8114e4448

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Project / Subsystem

gcc / tree-optimization

Date

2026-08-18

Author

Richard Biener

Commit

8ff8114e4448307f27e38fbdb98028283ab64f1c

Source

github

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Breaking

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All attributes

project: gcc
subsystem: tree-optimization
patch_id: —
commit_hash: 8ff8114e4448307f27e38fbdb98028283ab64f1c
source_type: github
headline: Fix crash in loop IV optimization due to missed folding
tldr: Avoid a crash in loop IV optimization when simplifying an induction variable candidate to zero.
author: Richard Biener
outcome: committed
performance_win: false
breaking_change: false
series_id: —
series_parts: []
tags: • optimization
• loop
• crashfix
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/8ff8114e4448307f27e38fbdb98028283ab64f1c
date: 2026-08-18T00:00:00.000Z

This commit addresses a crash in the loop invariant code (IVOPTs) optimization pass. Previously, if a simplification of an induction variable candidate resulted in a zero step, the Scalar Evolution (SCEV) analysis might still consider it an IV with a zero step. This change prevents a crash by handling cases where the IV is invariant.