rmake

rmake is a make-compatible build runner implemented in mruby with the explicit goal of building CRuby across platforms using a single make engine.

This repository is intentionally minimal today: we’re defining the MVP scope and scaffolding a clean, testable architecture so we can grow compatibility in a controlled way.

Goal

• Run enough of CRuby’s Makefiles to build a default CRuby on supported platforms.
• Prefer compatibility with standard make behavior first, then GNU Make where it matters.
• Keep the implementation small and testable; native extensions are used only when needed.

Quick Start (dev)

This is a mruby gem-style layout.

• mrbgem.rake defines the gem.
• mrblib/ contains the mruby sources.
• tools/rmake is the CLI entrypoint (invoked via mruby tools/rmake).

Rake Tasks

Use the top-level Rakefile for both tests and packaging:

rake -T

Main tasks:

• rake test (same as rake test:all)
• rake test:unit
• rake test:micro
• rake test:gnu
• rake build (same as rake build:rmake)
• rake build:rmake_no_clean
• rake rmake:clean

Build mruby

rmake ships a local mruby build under mruby/ and includes mruby-file-stat for fast File.mtime. File.mtime support is required.

cd mruby
make clean all

Run

/path/to/mruby/bin/mruby tools/rmake [options] [target] [VAR=VALUE]

Options:

• -f FILE Read FILE as a makefile
• -j N Run N jobs in parallel
• -n Dry-run (print commands without running)
• -q Question mode (exit 0/1/2 without running recipes)
• -d Trace target evaluation and skips

Single Binary (rmake)

Build a standalone rmake binary (contains mruby + rmake bytecode):

rake build:rmake

Output:

• dist/rmake-<os>-<arch> (or .exe on Windows)

Optional env vars:

• RMAKE_NO_CLEAN=1 skip mruby clean before build
• RMAKE_OUT_TAG=<tag> override output suffix
• CC=<compiler> override C compiler for launcher link
• RMAKE_EXTRA_LDFLAGS="..." extra linker flags
• RMAKE_TOOLCHAIN=<toolchain> force mruby toolchain (gcc, clang, etc)

Status

• Parser/evaluator/executor are in mrblib/ with a growing test suite.
• Standard make compatibility is the current focus before GNU make extensions.

Supported (today)

• Variable assignments: =, :=, +=
• Conditionals: ifeq, ifneq, else ifeq, else ifneq, else, endif
• Includes: include, -include, !include
• Targets and recipes, order-only prerequisites (|)
• Suffix rules like .c.o:
• .PHONY, .PRECIOUS, .DELETE_ON_ERROR
• VPATH search for prerequisites
• -j parallel builds (when Process.spawn is available)
• -n dry-run prints commands (even for @ lines, like GNU make)
• -d trace mode for debugging

Not Yet Supported

• GNU make functions like $(if ...), $(or ...), $(and ...), $(filter ...), $(eval ...), $(call ...)
• Pattern rules (%) and advanced automatic variables
• .ONESHELL, .SECONDEXPANSION, and other GNU make extensions

Tests

rake test

test/run_gnumake_compat.rb downloads GNU make's run_make_tests.pl at runtime (default URLs: https://cgit.git.savannah.gnu.org/cgit/make.git/plain/tests/run_make_tests.pl, https://raw.githubusercontent.com/mirror/make/master/tests/run_make_tests.pl). If tmp/run_make_tests.pl exists, it is used as-is and no download is attempted. Set RUN_MAKE_TESTS_FETCH=0 to forbid downloads (missing local file then fails).

tmp/ and work/ are scratch directories. They are intentionally ignored by git and can be removed at any time.

test/run_all.rb is the integrated suite runner. It executes:

• local regression tests (test/run.rb)
• gmake micro-compat tests (test/run_gnumake_compat.rb)
• GNU run_make_tests.pl selected categories via test/rmake-make-driver.pl

Useful env vars:

• GNU_MAKE_TESTS_DIR=/path/to/make/tests to use a pre-existing GNU test tree
• RMAKE_GNU_TESTS_FETCH=0 to disable automatic clone of GNU make tests
• RMAKE_GNU_CATEGORIES=cat1,cat2,... to run a subset of GNU categories
• RMAKE_GNU_PROGRESS_SEC=20 to print periodic progress while GNU categories run
• RMAKE_GNU_TIMEOUT=1200 to set timeout seconds for GNU categories step

CI Artifacts

.github/workflows/build-rmake.yml builds rmake artifacts for:

• Linux x86_64
• macOS x86_64
• macOS arm64
• Windows x86_64

Next

• Tighten standard make compatibility and fixture coverage
• Implement minimal GNU make functions required by CRuby build