Landing: d8164f4da406

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Project / Subsystem

gcc / gcc/match

Date

2026-10-02

Author

Andrea Pinski

Commit

d8164f4da406c5061075472961b3c448604eb686

Source

github

Perf win

Breaking

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All attributes

project: gcc
subsystem: gcc/match
patch_id: —
commit_hash: d8164f4da406c5061075472961b3c448604eb686
source_type: github
headline: Fix integer overflow pattern for abs((convert)a)
tldr: Corrected a GCC pattern for abs((convert)a) to prevent integer overflow and undefined behavior.
author: Andrea Pinski
outcome: committed
performance_win: false
breaking_change: false
series_id: —
series_parts: []
tags: • optimization
• integer overflow
• pattern matching
• undefined behavior
discussion_id_link: —
bugzilla_pr: —
url: https://github.com/gcc-mirror/gcc/commit/d8164f4da406c5061075472961b3c448604eb686
date: 2026-10-02T00:00:00.000Z

A pattern in GCC’s pattern matching for (trunc)abs((ext)a) was fixed to prevent potential integer overflow and undefined behavior. The pattern has been restricted to non-integral types, ensuring that integer types are handled by a separate, more appropriate pattern. This resolves a bug where casting from unsigned types could lead to incorrect results.