[fpc-devel] Compile fpc with llvm

[Jonas Maebe]

On 2026-07-18 15:27, Adriaan van Os via fpc-devel wrote:
> With success I have built and used an fpc-3.3.1 based LLVM compiler.
> The FPC LLVM Wiki <https://wiki.freepascal.org/LLVM> [1] says that
> "the compiler itself on x86-64 is about 10% faster when compiled with
> LLVM on an Intel Haswell processor, or 18% if you also enable
> link-time optimization." I could not find how to do that (build the
> compiler itself with llvm) as it requires starting with an fpc-3.2.2
> compiler.

You can add OVERRIDEVERSIONCHECK=1 to the make command disable the 
version check. It's not advertised because using it in general is not 
supported (only when building the exact same FPC revision from which the 
compiler was built).


Jonas