Claude Code v2.0.27 fails with SIGILL on Intel Mac without AVX2 support

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Found 2 possible duplicate issues:

1. https://github.com/anthropics/claude-code/issues/5864
2. https://github.com/anthropics/claude-code/issues/6143

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🤖 Generated with Claude Code

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I'm not using specifically Claude Code but I had the same issue today on my 2019 Mac Pro after Claude app automatically updated to the most recent version:

% /Applications/Claude.app/Contents/MacOS/Claude
2025-10-30 12:42:15 [info] Starting app {
  appVersion: '0.14.10',
  isPackaged: true,
  platform: 'darwin',
  arch: 'x64',
  nodeVersion: '22.19.0'
}
2025-10-30 12:42:15 [info] Starting app {
  appVersion: '0.14.10',
  isPackaged: true,
  platform: 'darwin',
  arch: 'x64',
  nodeVersion: '22.19.0'
}
2025-10-30 12:42:15 [info] App is installed, enabling initial check and auto-updates
2025-10-30 12:42:15 [info] Checking for updates
[FontLoader] Found fonts at: /Applications/Claude.app/Contents/Resources/fonts
[FontLoader] Loaded 4/4 fonts from /Applications/Claude.app/Contents/Resources/fonts
2025-10-30 12:42:15 [error] Sentry caught: {
  eventId: '077a09c6cdd84f99b9ccc504507c3c5c',
  type: 'Unknown',
  value: 'No message',
  stack: undefined
}
2025-10-30 12:42:16.107 Claude[95724:56117439] The running client is already the latest version.
Set active chat nil
2025-10-30 12:42:17 [info] Starting periodic extension update checks (interval: 21600000ms)
2025-10-30 12:42:17 [info] Checking 0 extensions via can_install API using stored metadata
2025-10-30 12:42:17 [info] can_install check completed: 0 extensions checked: [ [length]: 0 ]
2025-10-30 12:42:17 [info] Successfully fetched blocklist from https://claude.ai/api/organizations/de5f4028-649f-43ac-9148-1e1fdd3a4587/dxt/blocklist with 0 entries
2025-10-30 12:42:17 [info] Saved 1 blocklists with 0 entries
2025-10-30 12:42:17 [info] Successfully updated blocklist
2025-10-30 12:42:17 [info] Organization allowlist enabled: false
2025-10-30 12:42:17 [info] Updated allowlist enabled state: false
Set active chat nil
zsh: illegal hardware instruction  /Applications/Claude.app/Contents/MacOS/Claude

Temporary workaround: take older app version (I'm using 0.13.106) and create per-process rule in Little Snitch that prohibits access to googleapis.com domain which effectively disables auto-update feature without altering other Claude app functionality.

PS: Can't believe that I'm paying $100/mo to idiots who can't build Chromium with proper compiler options and can't properly test it on all supported platforms before shipping it to users 🤦‍♂️🤦‍♂️🤦‍♂️

PPS: It's also safe to create Little Snitch rules that blocks telemetry slop domains honeycomb.io and intercom.io

I have the same issue 👎 .. the console version seems to work fine but not the VSCode extension/UI version.

<img width="1510" height="1174" alt="Image" src="https://github.com/user-attachments/assets/07da5375-2628-4a5c-9f4e-4e730ad1c2f6" />

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Still not working in VSCode (CLI works fine)

<img width="2560" height="1354" alt="Image" src="https://github.com/user-attachments/assets/bbaddcc5-a5b0-4b1d-a143-c5926fa36cf6" />

here's also the log for this supershort session with CC in VSCode

Claude VSCode.log

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