Development environment

Compiler development requires LLVM 22, a C toolchain, Python for the test harness, and either an installed Prismio compiler or the committed bootstrap seed. Run setup commands from the compiler repository root: the bootstrap scripts resolve src, runtime, bootstrap, and third_party/llvm-paths.json relative to that checkout.

Required tools

• LLVM and Clang 22.x, including llc and the LLVM C development libraries.
• A platform linker and SDK appropriate for the host.
• Python 3.8 or newer for tests, packaging, and support scripts.
• Git and ordinary shell tooling.

tools/setup_llvm.py is the authoritative LLVM locator. --check reports without changing the checkout; --llvm-dir DIR adopts an existing installation; --force downloads even if discovery succeeds; and --version selects the exact supported 22.x package. A successful setup validates the headers and link library and records their paths for bootstrap.sh and bootstrap.ps1.

python3 tools/setup_llvm.py --check
python3 tools/setup_llvm.py

Do not assume that a system clang and an arbitrary llc form a supported pair. The backend is compiled with PRISMIO_LLVM_REAL_HEADERS; the loaded C API and the tools consuming emitted IR must agree on the LLVM major.

Choose the compiler explicitly

The test runner honors PRISMIO before PATH. Point it at the generation you intend to test:

PRISMIO=$PWD/.prismio/build/debug/prismio python3 tests/test_runner.py

If no installed compiler is available, build the first generation from the committed IR seed, then build two self-hosted generations:

tools/bootstrap.sh --seed --out build/gen0
tools/bootstrap.sh --compiler build/gen0 --out build/gen1
tools/bootstrap.sh --compiler build/gen1 --out build/gen2

Windows uses tools/bootstrap.ps1 with -Seed or -Compiler and -Out. The shell and PowerShell scripts compile the LLVM bridge and runtime support, consume the same source inventory, use a content-keyed object cache, link into a temporary path, and install the completed compiler atomically. PRISMIO_LLVM_DIR overrides recorded LLVM discovery. PRISMIO_OBJ_CACHE=0 disables the cache when investigating it.

For fixed-point work, use a named generation such as build/gen2. For the normal repository loop, use prismio build; build.ums routes project commands to .prismio/build/debug/prismio once the local host exists.

Validate the setup

build/gen2 --version
PRISMIO=$PWD/build/gen2 python3 tests/test_runner.py --list
PRISMIO=$PWD/build/gen2 python3 tests/test_runner.py test_92_field_view_provenance

--version prints Prismio, loaded LLVM, compiler executable, and the resolved standard-library directory. Treat an unexpected compiler or (none found) stdlib as a setup error before debugging the language change.

Platform notes

On macOS, Apple Clang supplies the SDK-aware linker while Homebrew LLVM commonly supplies llc and libraries. On Linux, install the matching LLVM development packages. On Windows, use the repository PowerShell bootstrap and packaging paths rather than translating shell commands by hand.

On macOS, debug builds can produce a .dSYM; on Linux, use the matching Clang/LLD development packages; on Windows, keep MSVC target and SDK selection consistent. Cross-target compilation also needs the target SDK via --sysroot and a matching runtime-<triple> package. LLVM target support alone does not provide a platform runtime.