This is an unofficial read-only mirror of the gem5 simulator. The upstream repository is stored in Mercurial at with an official git mirror at The mirror is updated at least hourly. Please consider contributing your changes to the upstream project.
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gabemblack systemc: Get rid of leftovers from unimplemented warnings past.
These warnings were removed when the functionality they warned about
was implemented, but there were some leftovers like unnecessary
includes and some helper functions which hid gem5 specific headers
from the ext directory.

Change-Id: Ic886ac0f1264687524e3a7b7eaab8836f318a5a2
Reviewed-by: Gabe Black <>
Maintainer: Gabe Black <>
Latest commit 0f368d5 Oct 11, 2018
Failed to load latest commit information.
build_opts scons: Make MOESI_CMP_directory the default ARM ruby protocol Jun 13, 2017
configs configs: Fix CPUClass typo in Oct 9, 2018
ext testlib: No catch of custom exceptions in sandbox Sep 5, 2018
include/gem5 util: resolve m5op name mismatching in m5op headers. Jan 9, 2018
src systemc: Get rid of leftovers from unimplemented warnings past. Oct 16, 2018
util util: Do not use $(PWD) in Makefiles Sep 26, 2018
.gitignore misc: Add util/ to .gitignore. Oct 5, 2017
.hgignore misc: Add dtb files to the ignore list for git and mercurial Feb 21, 2017
.hgtags tests: Add documentation for new testing code Aug 17, 2018
COPYING ruby: fix and/or precedence in slicc Mar 1, 2017
LICENSE copyright: Add code for finding all copyright blocks and create a COP… Jun 3, 2011
MAINTAINERS misc: Update MAINTAINERS with learning-gem5 tag Dec 6, 2017
SConstruct scons: remove as version check Sep 19, 2018


This is the gem5 simulator.

The main website can be found at

A good starting point is, and for
more information about building the simulator and getting started
please see and

To build gem5, you will need the following software: g++ or clang,
Python (gem5 links in the Python interpreter), SCons, SWIG, zlib, m4,
and lastly protobuf if you want trace capture and playback
support. Please see for more details
concerning the minimum versions of the aforementioned tools.

Once you have all dependencies resolved, type 'scons
build/<ARCH>/gem5.opt' where ARCH is one of ALPHA, ARM, NULL, MIPS,
POWER, SPARC, or X86. This will build an optimized version of the gem5
binary (gem5.opt) for the the specified architecture. See for more details and options.

With the simulator built, have a look at for more information on how to use

The basic source release includes these subdirectories:
   - configs: example simulation configuration scripts
   - ext: less-common external packages needed to build gem5
   - src: source code of the gem5 simulator
   - system: source for some optional system software for simulated systems
   - tests: regression tests
   - util: useful utility programs and files

To run full-system simulations, you will need compiled system firmware
(console and PALcode for Alpha), kernel binaries and one or more disk
images. Please see the gem5 download page for these items at

If you have questions, please send mail to

Enjoy using gem5 and please share your modifications and extensions.