This page shows you how to install the toolchain to build Mynewt OS applications that run native on Mac OS and Linux. The applications run on Mynewt's simulated hardware. It also allows you to run the test suites for all packages that do not require HW support.
Note: This is not supported on Windows.
If you have not already installed Homebrew from the newt tutorials pages, install it.
OS X ships with a C compiler called Clang. To build applications for the Mynewt simulator with, a different compiler is used as default: gcc.
$ brew install gcc ... ... ==> Summary 🍺 /usr/local/Cellar/gcc/5.2.0: 1353 files, 248M
Check the gcc version you have installed (either using brew or previously installed). The brew-installed version can be checked using brew list gcc. The default compiler.yml configuration file in Mynewt expects version 5.x for Mac users, so if the installed version is 6.x and you wish to continue with this newer version, modify the <mynewt-src-directory>/repos/apache-mynewt-core/compiler/sim/compiler.yml file to change the default gcc-5 defined there to gcc-6. In other words, replace the lines shown highlighted below:
# OS X. compiler.path.cc.DARWIN.OVERWRITE: "gcc-5" compiler.path.as.DARWIN.OVERWRITE: "gcc-5" compiler.path.objdump.DARWIN.OVERWRITE: "gobjdump" compiler.path.objsize.DARWIN.OVERWRITE: "objsize" compiler.path.objcopy.DARWIN.OVERWRITE: "gobjcopy"
with the following:
compiler.path.cc.DARWIN.OVERWRITE: "gcc-6" compiler.path.as.DARWIN.OVERWRITE: "gcc-6”
In case you wish to use Clang, you can change your <mynewt-src-directory>/repos/apache-mynewt-core/compiler/sim/compiler.yml to use Clang. Delete the gcc-5 DARWIN.OVERWRITE lines highlighted below.
# OS X. compiler.path.cc.DARWIN.OVERWRITE: "gcc-5" compiler.path.as.DARWIN.OVERWRITE: "gcc-5" compiler.path.objdump.DARWIN.OVERWRITE: "gobjdump" compiler.path.objsize.DARWIN.OVERWRITE: "objsize" compiler.path.objcopy.DARWIN.OVERWRITE: "gobjcopy"
NOTE: Both the newer gcc 6.x and Clang report a few warnings but they can be ignored.
FURTHER NOTE: Mynewt developers mostly use gcc 5.x for sim builds; so it may take a little while to fix issues reported by the newer compiler. One option is to disable warnings. To do that, remove the -Werror flag as an option for the compiler in the <mynewt-src-directory>/repos/apache-mynewt-core/compiler/sim/compiler.yml file as shown below.
compiler.flags.base: > -m32 -Wall -ggdb
You may alternatively choose to specify the precise warnings to ignore depending on the error thrown by the compiler. For example, if you see a [-Werror=misleading-indentation] error while building the sim image, add -Wno-misleading-indentation] as a compiler flag in the same line from the <mynewt-src-directory>/repos/apache-mynewt-core/compiler/sim/compiler.yml file.
compiler.flags.base: > -m32 -Wall -Werror -ggdb -Wno-misleading-indentation
A third option is to simply downgrade to gcc 5.x.
$ brew install gdb ... ... ==> Summary 🍺 /usr/local/Cellar/gdb/7.10.1: XXX files,YYM
NOTE: When running a program with gdb, you may need to sign your gdb executable. This page shows a recipe for gdb signing. Alternately you can skip this step and continue without the ability to debug your mynewt application on your PC.*
The below procedure can be used to set up a Debian-based Linux system (e.g., Ubuntu). If you are running a different Linux distribution, you will need to substitute invocations of apt-get in the below steps with the package manager that your distro uses.
$ sudo apt-get install gcc-multilib libc6-i386
$ sudo apt-get install gdb Reading package lists... Done Building dependency tree Reading state information... Done Suggested packages: gdb-doc gdbserver The following NEW packages will be installed: gdb ... Processing triggers for man-db (2.6.7.1-1ubuntu1) ... Setting up gdb (7.7.1-0ubuntu5~14.04.2) ...
At this point you have installed all the necessary software to build and run your first project on a simluator on your Mac OS or Linux computer. You may proceed to the Create Your First Project section or continue to the next section and install the cross tools for ARM.