blaise

Modern self-hosting Object Pascal compiler

TLDR

Compile a single Pascal source file

$ blaise --source [Hello.pas] --output [Hello]

Compile a project described by a project XML file

$ blaise --project [project.xml] --output [myapp]

Compile in a specific build profile (debug, release, ...)

$ blaise --project [project.xml] --config [debug] --output [myapp]

Emit QBE intermediate representation for inspection

$ blaise --source [Hello.pas] --emit-ir

Show version / help

$ blaise --version

SYNOPSIS

blaise --source file [--output file] [--emit-ir]blaise --project file [--config profile] [--output file]

Blaise is a modern, self-hosting Object Pascal compiler written from scratch with no dependency on Free Pascal or Delphi sources. It targets native code through the QBE backend (with an LLVM backend in development) and is named after Blaise Pascal, the mathematician for whom the original Pascal language is also named.The language Blaise compiles is a "Pascal for the 2020s": a single language mode (no separate Delphi/Free Pascal/Turbo dialects), a single string type using UTF-8 internally, Automatic Reference Counting instead of manual memory management, reified generics, and zero-GUID interfaces. The toolchain ships its own debug format (OPDF) for first-class debugger support.Two invocation styles are supported. --source compiles a single file in the spirit of fpc hello.pas and is most useful for tutorials and one-off programs. --project reads a structured XML project file describing units, search paths, library dependencies and build profiles, which is the recommended workflow for non-trivial applications.Blaise bootstraps itself: the published binary is produced by the previous version of the compiler compiling its own sources, and the project tracks byte-for-byte exact rebuild as a correctness invariant.

PARAMETERS

--source FILE

Compile a single Pascal source FILE.

--output FILE

Path of the output executable. Defaults to the source's basename when omitted.

--project FILE

Read build settings (units, search paths, libraries, defines) from FILE — typically project.xml.

--config PROFILE

Select a build profile defined inside the project file. Common values are debug and release.

--emit-ir

Stop after emitting QBE intermediate representation; useful for inspecting code generation.

--version

Print the compiler version and exit.

--help

Show usage information and exit.

CAVEATS

Blaise is a young, actively-developed compiler — language and compiler flags can change between releases. The current backend is QBE, which targets a small set of architectures (x86_64, arm64, riscv64); the LLVM backend that broadens architecture coverage is still under construction. Source compatibility with Delphi and Free Pascal code is intentionally not a goal: many programs from those ecosystems will not compile unmodified.

HISTORY

Blaise was created by Graeme Geldenhuys as a clean-slate Object Pascal compiler with the explicit goal of "no legacy baggage" — full ARC, unified UTF-8, and a single language mode. The project is hosted at github.com/graemeg/blaise and is distributed under an open-source license. It joins a long lineage of Pascal implementations dating back to Niklaus Wirth's original Pascal compiler at ETH Zurich in 1970.