---
title: "GitHub CodeQL build modes unsupported on macOS 27 and Xcode 27: 2026-10-09 | Harbyn"
description: "GitHub CodeQL build modes unsupported on macOS 27 and Xcode 27, announced Oct 9, 2026."
canonical: "https://harbyn.com/changes/github/2026-10-09-codeql-2-27-2-improves-c-go-rust-and-javascript-analysis-4"
last-updated: 2026-10-09
---

# GitHub CodeQL build modes unsupported on macOS 27 and Xcode 27

Markdown version of <https://harbyn.com/changes/github/2026-10-09-codeql-2-27-2-improves-c-go-rust-and-javascript-analysis-4>.

Breaking change - GitHub. medium severity. In effect.

CodeQL autobuild and manual build modes are not supported for compiled languages on macOS 27 with any Xcode version, or on macOS 26 with Xcode 27 selected, because Apple stopped shipping the multi-architecture binaries traced analysis needs. Use at most macOS 26 and Xcode 26 with these build modes.

## Facts

| Fact | Value |
| --- | --- |
| Vendor | [GitHub](https://harbyn.com/vendors/github.md) |
| Kind | Breaking change |
| Severity | medium |
| Status | In effect |
| Announced | Oct 9, 2026 |
| Added to Harbyn | Oct 9, 2026 |
| Lead time | No dated deadline |
| Vendor page | <https://github.blog/changelog/2026-10-09-codeql-2-27-2-improves-c-go-rust-and-javascript-analysis> |
| Review | Reviewed by a person, extracted by a model |

## Find it in your code

```sh
npx harbyn scan
```

This change names no identifier the scanner can match line by line, so the scan tells you whether your repository uses GitHub, from its packages and API hosts. Nothing leaves your machine.

## Sources

Where this event comes from: the page we read, when we read it, and the hash of that snapshot.

- <https://github.blog/changelog/feed/> (changelog, fetched 2026-10-09 22:43 UTC, sha256 `ae8354e61e4221bbe8b3135190028a8f59bcaecefaa7015365abe8775554520a`)

## Related changes

### More from GitHub

- [CodeQL Go library deprecates IfStmt.getCond](https://harbyn.com/changes/github/2026-10-09-codeql-2-27-2-improves-c-go-rust-and-javascript-analysis-2.md) (Deprecation, announced Oct 9, 2026)
- [CodeQL CLI error handling and output changes](https://harbyn.com/changes/github/2026-10-09-codeql-2-27-2-improves-c-go-rust-and-javascript-analysis-3.md) (Behavior change, announced Oct 9, 2026)
- [CodeQL Go control-flow graph changes may break custom queries](https://harbyn.com/changes/github/2026-10-09-codeql-2-27-2-improves-c-go-rust-and-javascript-analysis-5.md) (Breaking change, announced Oct 9, 2026)
- [Triage role users or higher can now archive pull requests](https://harbyn.com/changes/github/2026-10-08-triage-role-users-or-higher-can-now-archive-pull-requests.md) (Behavior change, announced Oct 8, 2026)

### Changes at other vendors

- [Amazon Selling Partner API: October listing attribute usage and enumeration value updates](https://harbyn.com/changes/amazon-sp-api/2026-10-14-sp-api-updates-new-listings-items-api-ivp-values-in-eu5-jp-and-ca-stores-oct-2.md) (effective Oct 26, 2026)
- [Supabase: four CBC-mode TLS 1.2 cipher suites will be removed from project HTTP APIs](https://harbyn.com/changes/supabase/2026-10-12-an-outdated-subset-of-tls-1-2-ciphers-will-be-disabled-on-project-http-apis.md) (effective Nov 10, 2026)
- [Google Workspace APIs: OAuth clients must be marked as agentic to call Google Workspace MCP servers](https://harbyn.com/changes/google-workspace/2026-10-12-oauth-clients-must-be-marked-as-agentic-to-call-google-workspace-mcp-servers.md) (effective Nov 11, 2026)
- [Bitbucket Cloud API: Git Credential Manager upgrade required for OAuth 2.0 Git authentication](https://harbyn.com/changes/bitbucket/2026-10-13-git-credential-manager-upgrade-required-for-oauth-2-0-git-authentication.md) (effective Nov 30, 2026)

[All upcoming deadlines](https://harbyn.com/deadlines.md)