GNU Assembler

It is used to assemble the GNU operating system and the Linux kernel, and various other software.

GAS is cross-platform, and both runs on and assembles for a number of different computer architectures.

GAS is free software released under the GNU General Public License v3.

GAS is often used as the assembler on Linux operating systems in conjunction with other GNU software.

A modified version of GAS can also be found in the macOS development tools package.