compiletools 13.0.0

SYNOPSIS

ct-* [compilation args] [filename.cpp] [–variant=<VARIANT>]

DESCRIPTION

compiletools provides C/C++ build automation with minimal configuration. The tools automatically determine source files, dependencies, and build requirements by analyzing your code.

To build a C or C++ project, simply type:

ct-cake

This automatically determines source files, builds executables, and runs tests. See ct-cake(1) for details.

QUICK START

Try compiletools without installing using uvx:

uvx --from compiletools ct-cake
uvx --from compiletools ct-compilation-database

This runs tools directly without affecting your system. All ct-* tools work with uvx (e.g., uvx --from compiletools ct-config).

INSTALLATION

uv pip install compiletools

Or for development:

git clone https://github.com/DrGeoff/compiletools
cd compiletools
uv pip install -e ".[dev]"

EXAMPLES

Two example trees ship with the package:

• src/compiletools/examples-end-to-end/ — buildable mini-projects exercising the full ct-cake --auto pipeline (PCH, C++20 modules, static / dynamic libraries, multi-target apps, sanitizer variants, pkg-config, …). Each has a README describing what it demonstrates; cd into one and run ct-cake to see the build flow end-to-end.

• src/compiletools/examples-features/ — focused, fixture-style projects for individual magic-flag annotations and config features (//#PKG-CONFIG=, //#LDFLAGS=, //#PCH=, //#GIT=, append-style variables, …). Useful as copy-paste templates when adding the same feature to your own project.

The examples_registry Python module (example_path(), example_file()) maps these trees from test code; tests under src/compiletools/test_*.py use them as fixtures, so each example is also a worked CI-verified configuration.

KEY FEATURES

Magic Comments

Embed build requirements directly in source files using special comments like //#LDFLAGS=-lpthread or //#PKG-CONFIG=zlib, or pull in an external git repository with //#GIT=<url>. See ct-magicflags(1) and the worked example in src/compiletools/examples-end-to-end/sudoku_tui/.

Automatic Dependency Detection

Traces #include statements to determine what to compile and link. No manual dependency lists needed.

Build Variants

Support for debug, release, and custom build configurations. Use --variant=release to select. See ct-config(1).

Pluggable Build Backends

Choose from the builtin Shake backend (default), Make, Ninja, CMake, or Bazel. Use --backend=<name> to select. See ct-backends(7).

Content-Addressable Caching

Objects, precompiled headers, C++20 module BMIs, and the linker artefacts themselves (executables, static libs, shared libs) are cached in per-variant content-addressable directories (cas-objdir, cas-pchdir, cas-pcmdir, cas-exedir). Cache keys are anchored to the git root, so identical translation units share entries even when the workspace is moved or cloned to a new path. Combined with the default --use-mtime=False, fresh-checkout CI builds (where every source has mtime=now) hit the cache instead of re-running the producer. Trim with ct-trim-cache.

C++20 Modules

First-class support for clang .pcm and gcc .gcm BMI artefacts – including named modules, partitions, header units, and import std – with automatic discovery from import / export module in your sources. See the C++20 Modules Caching section in ct-cake(1).

Precompiled Headers

Mark headers with //#PCH= and ct-cake builds them once and shares them across the project via cas-pchdir.

File Locking

Multi-user/multi-host object file caching with filesystem-aware locking for faster builds in team environments. Enable with file-locking = true.

Minimal Configuration

Works out-of-the-box with sensible defaults. Configuration only needed for customization.

CORE TOOLS

ct-cake

Main build tool. Auto-detects targets, builds executables, runs tests.

ct-compilation-database

Generate compile_commands.json for IDE integration. Auto-detects targets.

ct-config

Inspect configuration resolution and available compilation variants.

ct-magicflags

Show magic flags extracted from source files.

ct-fetch

Clone, update, or report the //#GIT= external git repositories a target tree depends on, without running a build.

ct-headertree

Visualize include dependency structure.

ct-filelist

Generate file lists for packaging and distribution.

ct-timing-report

Analyze build timing data from ct-cake --timing. Interactive TUI, static summary, run comparison, and Chrome Trace export.

ct-trim-cache

Trim aged entries from the object, PCH, PCM, and linker-artefact content-addressable caches with configurable retention.

ct-cache-report

Summarize content-addressable cache occupancy and flag duplication in the object, PCH, PCM, and linker-artefact caches.

ct-debug-pcm-hash-inputs

Dump the seven inputs that drive a C++20 module BMI’s <cas-pcmdir>/<cmd_hash>/ cache path as JSON. Run twice across back-to-back ct-cake invocations and diff the outputs to identify which input drifted when a BMI lands under a fresh subdir on unchanged source.

ct-cas-publish

Helper invoked from generated build recipes: atomically publish a cas-exedir entry to a user-facing bin/<variant>/<name> path via link() + rename(), with EXDEV-only symlink fallback. Not normally run by hand.

ct-cleanup-locks

Clean stale locks from file locking.

ct-check-venv

Verify that the ct-cake on PATH imports the same compiletools as the active venv. Run after git worktree add and a fresh uv pip install -e . to confirm subprocess-driven tools see the expected source tree.

ct-list-backends

List available build backends (make, ninja, cmake, bazel, shake).

Shell Wrappers

Convenience scripts in scripts/: ct-build, ct-build-static-library, ct-build-dynamic-library, ct-watch-build, ct-lock-helper, ct-release.

CONFIGURATION

Options are parsed using ConfigArgParse, allowing configuration via command line, environment variables, or config files.

Configuration hierarchy (lowest to highest priority):

• Executable directory (ct/ct.conf.d alongside the ct-* executable)

• System config (/etc/xdg/ct/)

• Python virtual environment (${python-site-packages}/ct/ct.conf.d)

• Package bundled config (<installed-package>/ct.conf.d)

• User config (~/.config/ct/)

• Project config (<gitroot>/ct.conf.d/)

• Git repository root directory

• Current working directory, and the nearest-ancestor ct.conf / ct.conf.d of every explicit or –auto-discovered build target (target-anchored layers; same priority tier as the current working directory)

• Environment variables (capitalized, e.g., VARIANT=release)

• Command-line arguments

All loaded configuration applies to the whole invocation — there is no per-translation-unit scoping. Because target-anchored layers and the current-working-directory layer share one tier, they must agree: if two same-tier config files set the same key to different values (including append-/prepend- keys), the tools stop with an error naming both files and the two remedies (build the subprojects separately, or make the values identical).

For a target outside any git repository (or under --no-git-root) the ancestor walk is bounded only by the filesystem root; a layer it finds at or above your home directory triggers an unconditional ct: warning: because such a file (e.g. a forgotten ~/ct.conf) is almost certainly stray — legitimate user-level config belongs in ~/.config/ct/.

Build variants are composed from axis conf files — one per orthogonal concern: toolchain (gcc, clang), linker (ld, gold, mold, wild), optimization (debug, release), instrumentation (asan, ubsan, tsan, coverage, lto). --variant=gcc,debug,asan (or gcc.debug.asan or gcc debug asan — comma, dot, and whitespace are all equivalent) synthesizes the composition from gcc.conf + debug.conf + asan.conf. No per- combination conf file is required.

Common usage:

ct-cake --variant=gcc,release             # toolchain + opt
ct-cake --variant=clang,debug,asan        # toolchain + opt + sanitizer
ct-cake --variant=gcc,mold,release,lto    # everything composes
ct-cake --append-CXXFLAGS="-march=native"

For details on configuration hierarchy, file format, and variant system, see ct-config(1).

ATTRIBUTION

This project is derived from the original compiletools developed at Zomojo Pty Ltd (between 2011-2019). Zomojo ceased operations in February 2020. This repository continues the development and maintenance of the compiletools project.

SEE ALSO

• ct-backends (7) – build backend architecture and selection guide

• ct-build

• ct-build-docs

• ct-build-dynamic-library

• ct-build-static-library

• ct-cake

• ct-cas-publish

• ct-check-venv

• ct-cleanup-locks

• ct-compilation-database

• ct-config

• ct-cppdeps

• ct-create-makefile

• ct-debug-pcm-hash-inputs

• ct-fetch

• ct-filelist

• ct-findtargets

• ct-git-sha-report

• ct-gitroot

• ct-headertree

• ct-jobs

• ct-list-backends

• ct-list-variants

• ct-lock-helper

• ct-magicflags

• ct-pytest-monitor

• ct-release

• ct-timing-report

• ct-trim-cache

• ct-watch-build