Building GHDL from Sources

Download

GHDL can be downloaded as a zip-file/tar-file (latest ‘master’ branch) or cloned with git clone from GitHub. GitHub offers HTTPS and SSH as transfer protocols. See the Downloading Source Files page for further details.

Important

Since GHDL is written in Ada, independently of the code generator you use, the a compiler is required. Most GNU/Linux package managers provide a package named gcc-ada or gcc-gnat. Alternatively, GNU Ada compiler, GNAT GPL, can be downloaded anonymously from libre.adacore.com (2014, or later; for x86, 32 or 64 bits). Then, untar and run the doinstall script.

Attention

Since v0.37, GHDL’s synthesis features require GCC >=8.1, due to some new GNAT features which are not available in previous releases. Users with older versions (who don’t need synthesis) can configure GHDL with option --disable-synth.

Available back-ends

GHDL currently supports three different back-ends (code generators):

  • mcode - built-in x86 (or x86_64) code generator
  • GCC - Gnu Compiler Collection (gcc.gnu.org)
  • LLVM - Low-Level Virtual Machine (llvm.org)

Here is a short comparison, so that you can choose the one you want to use:

Back-end Pros Cons
mcode
  • Very easy to build
  • Very quick analysis
  • Can handle very large designs
  • Simulation is slower
  • x86_64/i386 only
LLVM
  • Generated code is faster
  • Generated code can be debugged (with -g)
  • Easier to build than GCC
  • Ported to many platforms (x86, x86_64, armv7/aarch64)
  • Build is more complex than mcode
GCC
  • Generated code is faster (particularly with -O or -O2)
  • Generated code can be debugged (with -g)
  • Ported to many platforms (x86, x86_64, PowerPC, SPARC)
  • Build is even more complex
  • Analysis can take time (particularly for large units)
  • Code coverage collection (gcov) is unique to GCC

Hint

The output of both GCC and LLVM is an executable file, but mcode does not generate any. Therefore, if using GCC/LLVM, the call with argument -r can be replaced with direct execution of the binary. See section Quick Start Guide.

After making your choice, you can jump to the corresponding section. However, we suggest you to read Directory structure first, so that you know where the content will be placed and which files are expected to be created.

Hint

In these instructions, the configure script is executed in the source directory; but you can execute in a different directory too, like this:

$ mkdir ghdl-objs
$ cd ghdl-objs
$ ../path/to/ghdl/configure ...

Hint

On Windows, building GHDL with mcode backend and GNAT GPL 32 bit seems to be the only way to get a standalone native executable.

  • MINGW/MSYS2 builds depend on the environment/runtime.

Hint

For MacOS 10.15 (Catalina), see https://github.com/ghdl/ghdl/issues/1368 for workarounds to link failures.