PR 34165 aarch64 assertion fail and segv

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Project / Subsystem

binutils / binutils

Date

2026-07-01

Proposer

Alan Modra <amodra@gmail.com>

Source type

public_inbox

Consensus

Proposed

Sentiment

—/10

Technical tradeoffs

• Fixes a crash by relaxing an assertion, potentially masking underlying issues with weak undefined TLS symbol handling.
• Aligns AArch64 behavior with x86 for specific TLS symbol scenarios.

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All attributes

project: binutils
subsystem: binutils
patch_id: —
discussion_id: akTVYb32aOjEDV8W@squeak.grove.modra.org
source_type: public_inbox
title: PR 34165 aarch64 assertion fail and segv
headline: PR 34165 aarch64 assertion fail and segv
tldr: Fixes an assertion failure and segfault in aarch64 ELF linking related to weak undefined TLS symbols.
proposer: Alan Modra <amodra@gmail.com>
consensus: Proposed
outcome: proposed
sentiment_score: —
technical_tradeoffs: • Fixes a crash by relaxing an assertion, potentially masking underlying issues with weak undefined TLS symbol handling.
• Aligns AArch64 behavior with x86 for specific TLS symbol scenarios.
series_id: —
series_role: standalone
series_parts: []
tags: • aarch64
• elf
• linker
• tls
• bugfix
url: https://inbox.sourceware.org/binutils/akTVYb32aOjEDV8W@squeak.grove.modra.org
bugzilla_url: —
date: 2026-07-01T00:00:00.000Z

PR 34165 aarch64 assertion fail and segv

This patch resolves an assertion failure and subsequent segmentation fault in binutils’ AArch64 ELF linker. The issue arises when weak undefined TLS symbols are used, as their addresses are tied to the thread pointer. The fix modifies the dtpoff_base and tpoff_base functions to return 0 instead of asserting that tls_sec is non-NULL, thus preventing the crash and resulting in a zero .got entry for these symbols, consistent with x86 behavior.