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xPack GNU RISC-V Embedded GCC v8.3.0-1.2 released

· 6 min read
Liviu Ionescu (ilg)
Liviu Ionescu (ilg)

Version 8.3.0-1.2 is a maintenance release of the xPack GNU RISC-V Embedded GCC, that packs the SiFive release from August 2019, and adds support for running on Arm platforms, like Raspberry Pi.

This is the xPack distribution of the SiFive RISC-V GCC.

There are separate binaries for Windows, macOS and GNU/Linux, 32/64-bit.

Starting with this version, support for 32/64-bit Arm GNU/Linux platforms, like Raspberry Pi, was added.

Download​

The binary files are available from GitHub Releases.

Install​

The easiest way to install this specific version, is by using xpm:

xpm install @xpack-dev-tools/riscv-none-elf-gcc@8.3.0-1.2.1 -verbose

The full details of installing the xPack GNU RISC-V Embedded GCC on various platforms can be found in the Install Guide.

Compliance​

Starting with v8.2.0-2, this distribution closely follows the official SiFive Freedom Tools distribution.

This release is based on the v2019.08.0 release, and includes the SiFive extensions (like CLIC interrupts and a an even larger multi-lib set).

The following commits (from sifive/freedom-tools) were used:

GDB was upstreamed and does not require SiFive specific patches, so the current build uses git://sourceware.org/git/binutils-gdb.git, the 9b40759 commit from 28 Feb 2019.

Supported libraries​

The supported libraries are:

$ riscv-none-embed-gcc -print-multi-lib
.;
rv32e/ilp32e;@march=rv32e@mabi=ilp32e
rv32ea/ilp32e;@march=rv32ea@mabi=ilp32e
rv32em/ilp32e;@march=rv32em@mabi=ilp32e
rv32eac/ilp32e;@march=rv32eac@mabi=ilp32e
rv32emac/ilp32e;@march=rv32emac@mabi=ilp32e
rv32i/ilp32;@march=rv32i@mabi=ilp32
rv32ia/ilp32;@march=rv32ia@mabi=ilp32
rv32im/ilp32;@march=rv32im@mabi=ilp32
rv32if/ilp32f;@march=rv32if@mabi=ilp32f
rv32ifd/ilp32d;@march=rv32ifd@mabi=ilp32d
rv32iaf/ilp32f;@march=rv32iaf@mabi=ilp32f
rv32iafd/ilp32d;@march=rv32iafd@mabi=ilp32d
rv32imaf/ilp32f;@march=rv32imaf@mabi=ilp32f
rv32imf/ilp32f;@march=rv32imf@mabi=ilp32f
rv32imfd/ilp32d;@march=rv32imfd@mabi=ilp32d
rv32iac/ilp32;@march=rv32iac@mabi=ilp32
rv32imac/ilp32;@march=rv32imac@mabi=ilp32
rv32imafc/ilp32f;@march=rv32imafc@mabi=ilp32f
rv32imafdc/ilp32d;@march=rv32imafdc@mabi=ilp32d
rv64i/lp64;@march=rv64i@mabi=lp64
rv64ia/lp64;@march=rv64ia@mabi=lp64
rv64im/lp64;@march=rv64im@mabi=lp64
rv64if/lp64f;@march=rv64if@mabi=lp64f
rv64ifd/lp64d;@march=rv64ifd@mabi=lp64d
rv64iaf/lp64f;@march=rv64iaf@mabi=lp64f
rv64iafd/lp64d;@march=rv64iafd@mabi=lp64d
rv64imf/lp64f;@march=rv64imf@mabi=lp64f
rv64imaf/lp64f;@march=rv64imaf@mabi=lp64f
rv64iac/lp64;@march=rv64iac@mabi=lp64
rv64imac/lp64;@march=rv64imac@mabi=lp64
rv64imafc/lp64f;@march=rv64imafc@mabi=lp64f
rv64imafdc/lp64d;@march=rv64imafdc@mabi=lp64d

Bug fixes​

  • none

Improvements​

Compared to the original SiFive version, the same architecture and API options are supported, and there are minimal functional changes

  • libgloss was removed from the list of libraries always linked to the application, since it issues ECALL instructions that fail in bare metal environments
  • march=rv32imaf/mabi=ilp32f was added to the list of multi-libs
  • the standard documentation, in PDF and HTML, is included
  • experimental support for Python in GDB was added

newlib-nano​

Support for newlib-nano is available using the --specs=nano.specs option. For better results, this option must be added to both compile and link time.

nosys.specs​

If no syscalls are needed, --specs=nosys.specs can be used at link time to provide empty implementations for the POSIX system calls.

Compile options​

The libraries are compiled with -O2 -mcmodel=medany. The nano version is compiled with -Os -mcmodel=medany.

caution

It is mandatory for the applications to be compiled with -mcmodel=medany, otherwise the link will fail.

Python​

Support for Python scripting was added to GDB. This distribution provides two separate binaries, riscv-none-embed-gdb-py with Python 2.7 support, and riscv-none-embed-gdb-py3 with support for Python 3.7.

It is mandatory to have exactly these version installed, otherwise GDB will not start properly.

For this it is recommended to install the binaries provided by Python, not those available in the distribution, since they may be incomplete, for example those in Ubuntu/Debian, which split the Python system library into multiple packages.

On GNU/Linux, the recommended way is to build is from sources, and install locally:

python3_version="3.7.9"
mkdir -p "${HOME}/Downloads"
curl -L --fail -o "${HOME}/Downloads/Python-${python3_version}.tgz" https://www.python.org/ftp/python/${python3_version}/Python-${python3_version}.tgz
rm -rf "${HOME}/Work/Python-${python3_version}"
mkdir -p "${HOME}/Work"
cd "${HOME}/Work"
tar xzf "${HOME}/Downloads/Python-${python3_version}.tgz"
cd "${HOME}/Work/Python-${python3_version}"
bash ./configure --prefix="${HOME}/opt"
make
make altinstall

To run GDB with this version of Python, use a script to set the proper environment, like:

mkdir -p "${HOME}/opt/bin"
cat <<'__EOF__' > "${HOME}/opt/bin/riscv-none-embed-gdb-py3.sh"
#!/usr/bin/env bash
PYTHONPATH="$($HOME/opt/bin/python3.7 -c 'import os; import sys; print(os.pathsep.join(sys.path))')" \
PYTHONHOME="$($HOME/opt/bin/python3.7 -c 'import sys; print(sys.prefix)')" \
riscv-none-embed-gdb-py3 "$@"
__EOF__
chmod +x "${HOME}/opt/bin/riscv-none-embed-gdb-py3.sh"

Text User Interface (TUI)​

Support for TUI was added to GDB. The ncurses library (v6.2) was added to the distribution.

note

TUI is not available on Windows

Known problems​

  • the GDB binaries with Python support were built with version 2.7/3.7, and require exactly those versions in order to run properly.

Documentation​

The original PDF documentation is available in the share/doc folder.

Supported platforms​

Binaries for Windows, macOS and GNU/Linux are provided.

The binaries were built using the xPack Build Box (XBB), a set of build environments based on slightly older distributions, that should be compatible with most recent systems.

  • x86/x64 GNU/Linux: all binaries were built with GCC 9.3, running in an Ubuntu 12 Docker container
  • arm64/arm GNU/Linux: all binaries were built with GCC 9.3, running in an Ubuntu 16 Docker container
  • x86/x64 Windows: all binaries were built with mingw-w64 GCC 9.3, running in an Ubuntu 12 Docker container
  • x64 macOS: all binaries were built with GCC 9.3, running in a separate folder on macOS 10.10.5.

Build​

The scripts used to build this distribution are in:

  • distro-info/scripts

For the prerequisites and more details on the build procedure, please see the README-MAINTAINER page.

Travis tests​

The first set of tests were performed on Travis, by running a simple script to check if the binaries start and compile several simple programs on a wide range of platforms and distributions:

Tests​

The binaries were testes on Windows 10 Pro 32/64-bit, Ubuntu 18 LTS 64-bit, Xubuntu 18 LTS 32-bit and macOS 10.14.

The tests consist in building and debugging some simple Eclipse projects available in the build project.

Since the source code used for GCC is identical to the one used by SiFive, the long and complex tests performed by SiFive to validate their release were not executed again.

Checksums​

The SHA-256 hashes for the files are:

2009f256e59291e1025cc099e4300d7662dda040b304fe3462b4cb7c35c71378
xpack-riscv-none-embed-gcc-8.3.0-1.2-darwin-x64.tar.gz

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xpack-riscv-none-embed-gcc-8.3.0-1.2-linux-arm64.tar.gz

63f232cbeddbe968130f4c8386cca24c5e1410cc2551738d071b279a94cd8b75
xpack-riscv-none-embed-gcc-8.3.0-1.2-linux-arm.tar.gz

1d99730d6e1e5d3a60fa0ccfbbcf0276e77dd83d58b6d8d1543cef40a1dd96ca
xpack-riscv-none-embed-gcc-8.3.0-1.2-linux-x32.tar.gz

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xpack-riscv-none-embed-gcc-8.3.0-1.2-linux-x64.tar.gz

8e7e98117900f3eed717b20555b346c2473dcbb9090e05c456412008f39fb62d
xpack-riscv-none-embed-gcc-8.3.0-1.2-win32-x32.zip

5b7a4e3a2bb22566fed951972d726d10ff43bc35db17f9287eed52766e80ecee
xpack-riscv-none-embed-gcc-8.3.0-1.2-win32-x64.zip

Download analytics​

Credit to Shields IO for the badges and to Somsubhra/github-release-stats for the individual file counters.