Miosix Toolchain
Information on the Miosix Toolchain
The Miosix Toolchain is a patched version of the GCC compiler, Newlib C library, and libstdc++ library. The main purpose of the Miosix-specific patches to the compiler and standard libraries is to provide thread safety of the C and C++ language and libraries by teaching GCC the Miosix thread model. Additional goals of these patches are to improve speed of certain library functions and reduce code size.
The use of the patched compiler is mandatory for compiling Miosix. The compiler patches are updated from time to time, and users are required to upgrade to the latest version of the compiler when necessary. The build system will warn you when it's time to upgrade the compiler.
Latest version of the Miosix Toolchain
Released 08/06/2014. This version adds sys/ioctl.h and sys/termios.h to the C library. It is a mandatory release, newer kernels won't build with previous compiler. There are no bug fixes.
_MIOSIX_GCC_PATCH_VERSION is set to 1 in this release.
You can download it here
- Miosix Toolchain Linux (sha1sum 6952ce2106e5a6f830a250b9b384e8dba0fe4100) This is self-installing shell script, run it with
sh MiosixToolchainInstaller.run
- Miosix Toolchain Windows (sha1sum 9750cef4593c5eb5df8fc497cdd888d33f1e006d) This is a self-installing .exe
Both versions will automatically detect a previous version of the compiler and uninstall it, unless you are on Linux and you have installed the toolchain from sources. In such a case you should uninstall it manually using the uninstall.sh file in the miosix/_tools/compiler directory of the kernel git repository.
Previous version of the Miosix Toolchain
Released 06/04/2014. This is the first version of the Miosix Toolchain available as a binary self-installing package.
_MIOSIX_GCC_PATCH_VERSION is not defined in this release.
You can download it here
- Miosix Toolchain Linux (sha1sum 359878b78f2c462f0ce1d207b837d2313968b443) This is self-installing shell script.
- Miosix Toolchain Windows (sha1sum a62cb3fa628f6ca47f1c8e248c0cf24d41bc28aa) This is a self-installing .exe
The patches to the compiler and standard libraries are required to:
- Provide thread safety of the C and C++ libraries. A lot of potential race conditions that occur when GCC is built for an embedded platform (i.e: not to produce binaries for a mainstream OS such as Linux or Windows where thread safety issues are already dealt with) have been fixed, for exemple throwing C++ exception from more threads at the same time is now thread safe, constructors of static objects are now thread safe, accessing the same FILE * handle from more threads is now thread safe... This cannot be done by the compiler alone, nor by the kernel alone, cooperation of the two is required, and this is the number one reason for having patches.
- Improved speed of the pthread API. For example, pthread_mutex_t is no longer an opaque pointer type but the real struct containing the mutex implementation. This results in a 7x speed increase with respect to the previous pthread_mutex code.
- Some more code size and RAM requirement reductions, such as the redefinition of BUFSIZ from 1024 to 256 bytes which reduces the RAM used by the C stdio library.
Some of the patches, mainly those that increase performance and reduce code size in Newlib have also been contributed upstream, but to date compiling Miosix still requires patches.
In previous versions of the kernel, the user was required to download the compiler sources, patch it and compile it. Even though this was automated through a simple script, it took a long time to build the compiler, especially for older machines, and it was cumbersome to say the least to do it on Windows. Starting from Miosix 2.0, the compiler is also distributed as a self-installing precompiled package, for both Linux and Windows.