graemeg/blaise

Source: https://github.com/graemeg/blaise

= Blaise Pascal Compiler :icons: font :source-highlighter: rouge

The Pascal you love, reimagined for the modern era.

Blaise is a next-generation Object Pascal compiler built from the ground up to eliminate decades of legacy baggage. It prioritizes developer productivity, memory safety, and high-performance execution.

== ✨ The Vision

The Object Pascal ecosystem has two options: Embarcadero Delphi (proprietary, Windows-first) and Free Pascal (open source but carrying 30 years of accumulated complexity — five language modes, five string types, and thousands of include files).

This compiler takes a different approach:

• One language mode. No {$mode} switches; no legacy dialect support.
• One string type. UTF-8 reference-counted string. RawBytes for binary data.
• One memory model. Automatic reference counting applies uniformly to strings, classes, and interfaces. No manual/auto split between TObject and TInterfacedObject; [Weak] breaks cycles. Free is retained as a synonym for immediate release.
• Clean interfaces. No COM GUIDs; interface dispatch via compile-time vtable mapping.
• Reified generics. Monomorphization at compile time — no type erasure.
• Modern build system. PasBuild with project.xml; no makefiles.
• First-class debugger. OPDF is the default debug format; DWARF is not required.

See link:docs/design.adoc[docs/design.adoc] for the full architecture and implementation plan.

The result — A modern, cross-platform Object Pascal compiler targeting native code via https://c9x.me/compile/[QBE] (and eventually LLVM). Single language mode, single string type, zero-GUID interfaces, reified generics, and first-class https://github.com/graemeg/opdebugger[OPDF] debug format support.

== 🚀 Project Status

• Self-Hosting: Yes. Blaise currently bootstraps and recompiles itself with byte-for-byte exact matches.
• Testing: 1200+ tests and growing (Test-Driven Development from day one).
• Backends: Currently utilizing a QBE backend, with an LLVM backend in active development.

[cols=“1,3,1”, options=“header”] |=== | Phase | Goal | Status

| 1 | Bootstrap pipeline — Hello World on Linux x86_64 via PasBuild | Complete ✅

| 2 | Type system — classes, records, ARC, exceptions | Complete ✅

| 3 | Generics + zero-GUID interfaces | Complete ✅

| 4 | OPDF debug info emission | Complete ✅

| 5 | Self-hosting + LLVM + Windows + macOS ARM64 | In-Progress

| 6 | LSP + VS Code extension | Planned

| 7 | Migration analyser for FPC/Delphi codebases | Planned |===

== What Is Dropped From Classic Pascal

[cols=“1,3”, options=“header”] |=== | Feature | Reason for removal

| ShortString, AnsiString, WideString, UnicodeString | Replaced by a single UTF-8 reference-counted string type

| with statement | Source of hard-to-diagnose symbol resolution bugs; breaks static analysis

| Old-style object types | Use record (stack/value) or class (heap/reference) instead

| COM-style interface GUIDs | Interface dispatch via compile-time vtable; GUIDs are unnecessary complexity

| Multiple language modes | One dialect, maintained well, beats five dialects maintained poorly

| assign, reset, rewrite, blockread | Replaced by a stream-based I/O RTL

| TObject vs TInterfacedObject split | One unified class model under automatic reference counting; [Weak] breaks cycles |===

== 📢 Community

The core architecture is still being finalised, so the project is not yet accepting code contributions. Feedback on language design, syntax choices, and the future direction of Blaise is very welcome — please use the https://github.com/graemeg/blaise/discussions[Discussions] tab on GitHub.

== Repository Layout

This project uses PasBuild’s multi-module layout. Each subdirectory with a project.xml is an independent module; the root project.xml is the aggregator.

…. project.xml Root aggregator (packaging=pom) │ ├── compiler/ The compiler binary (packaging=application) │ ├── project.xml │ └── src/ │ ├── main/pascal/ uLexer, uParser, uAST, uCodeGenQBE, … │ └── test/pascal/ FPTest test suite for compiler units │ ├── rtl/ Runtime library (packaging=library) │ ├── project.xml │ └── src/ │ ├── main/pascal/ System.pas, SysUtils.pas, Classes.pas, … │ └── test/pascal/ FPTest test suite for RTL units │ ├── tools/ │ └── migration-analyser/ FPC/Delphi migration report tool (packaging=application) │ ├── project.xml depends on compiler module │ └── src/ │ ├── main/pascal/ │ └── test/pascal/ │ ├── vendor/qbe/ Vendored QBE backend source (pinned, built from source) └── docs/ Design documents and specifications ….

PasBuild compiles each module to its own target/ subdirectory. Build output is never committed to the repository.

== Building

=== Prerequisites

• Free Pascal Compiler 3.2.2 or later (stable; 3.3.x development snapshots are not required)
• https://github.com/graemeg/pasbuild[PasBuild]
• A C compiler (gcc or clang) for building the vendored QBE backend
• GNU ld or lld (Linux); ld (macOS)

=== Build all modules

[source,shell]

pasbuild compile

PasBuild resolves the module dependency order automatically and compiles rtl → compiler → tools/migration-analyser.

=== Build with a profile

[source,shell]

pasbuild compile -p debug # includes -g -gl -Criot -gh pasbuild compile -p release # includes -O2 -CX -XX -Xs

=== Run tests

[source,shell]

pasbuild test

=== Build a single module

[source,shell]

pasbuild compile -m blaise-compiler

=== Running the compiler

Once built, the compiler binary is at compiler/target/blaise.

[source,shell]

Compile a single file

compiler/target/blaise –source Hello.pas –output Hello

Compile via project.xml

compiler/target/blaise –project project.xml –config debug –output myapp

Emit QBE IR (useful for debugging the compiler itself)

compiler/target/blaise –source Hello.pas –emit-ir

== Licence

Apache License v2.0 with Runtime Library Exception. See link:LICENSE[LICENSE].

Built with ❤️ for the Pascal community by Graeme.