Skip to content
Latchkey

SIGILL (Signal 4): Meaning, Exit Code 132 & Fix

SIGILL is Unix signal 4. A process terminated by it reports exit code 132 (128 + 4).

SIGILL fires when a process runs an instruction the CPU cannot execute. When it kills a process, the shell reports exit code 132 - the 128 + signal-number convention.

What it means

Usually a binary compiled for the wrong architecture or CPU feature level (e.g. AVX on a CPU without it).

When it happens in CI

  • Running an x86-64-v3 binary on an older runner CPU.
  • A corrupted or arch-mismatched binary/dependency.

How to handle it

Rebuild for the target CPU baseline, or pin a runner whose CPU supports the required instruction set.

Related guides

Run this faster and cheaper on Latchkey managed runners. Start free →