How to build

Dependencies

To build re2c from a release tarball one needs only a C++ compiler and Python 3 (for build-time scripts and for testing). Building on Windows additionally requires either CMake or a Mingw build environment.

To develop re2c one also needs CMake or Autotools (both build systems are maintained). Other dependencies include Bison (to rebuild parsers), Python 3 Docutils (to rebuild documentation) and Sphinx (to rebuild the website). Benchmarks also use Google-benchmark, re2 and Java. A few helper scripts are written in Haskell, but they are not essential for re2c development.

re2c is a self-hosting lexer generator, meaning that parts of its source code are written in re2c (namely, all the source files that have a .re extension). By default re2c builds from pre-generated bootstrap files. To build from source .re files, it is necessary to reconfigure the build and provide a path to an existing re2c binary that will be used for bootstrap (see the details below).

Build (Autotools)

If you are building from a release tarball, the configure script is already there. Otherwise it is necessary to generate it:

$ autoreconf -i -W all

An in-tree build (objects are generated side by side with sources):

$ ./configure && make && make install

An out-of-tree build (objects are generated in a separate directory):

$ mkdir .build && cd .build && ../configure && make && make install

The configure script has many options (to see them all, run configure --help). The options specific to re2c are the following:

  • --enable-debug Enable debug checks in the re2c source code. Also enables debug options.

  • --enable-golang Build re2go (identical to re2c --lang go). This is on by default.

  • --enable-rust Build re2rust (identical to re2c --lang rust). This is on by default.

  • --enable-lexers Enable regeneration of lexers from .re files (as opposed to using pre-generated bootstrap files). This requires setting RE2C_FOR_BUILD to an existing re2c executable path.

  • --enable-parsers Enable regeneration of parsers from .ypp files with bison (as opposed to using pre-generated bootstrap files).

  • --enable-docs Enable regeneration of documentation (requires Python 3 Docutils).

  • --enable-benchmarks Build benchmarks (requires Google benchmarks library).

  • --enable-benchmarks-regenerate Regenerate C code for Ragel and Kleenex benchmarks (this will download and build Ragel and Kleenex). re2c benchmarks are always regenerated.

  • --enable-libs Build the experimental libre2c library that provides POSIX regcomp/regexec/regfree interface to re2c.

Cross-compile re2c for Windows (for some Mingw versions you might have to use -std=gnu++11 compiler option):

$ ./configure --host i686-w64-ming32 \
    LDFLAGS="-static -static-libstdc++ -static-libgcc"

There is a bunch of build scripts for specialized builds with Asan, Ubsan, GLIBCXX_DEBUG, etc. in the build subdirectory.

Build (CMake)

re2c includes CMake presets for Linux, MacOS, and Windows. Use cmake --list-presets to see them.

  • The -fast presets have minimal dependencies and build re2c using pre-generated manpages, lexers, and parsers.

  • The -full presets have additional prerequisites (Docutils, Bison, and a pre-existing re2c binary) and re-generate the manpages, lexers, and parsers.

If you just want to build re2c, use the -release-ootree-fast preset. The other presets are primarily of interest to developers.

For example, to build the windows-msvc-release-ootree-fast preset:

  • CD to the root of the re2c folder (the folder containing this README).

  • Configure: cmake --preset=windows-msvc-release-ootree-fast

  • Build: cmake --build --preset=windows-msvc-release-ootree-fast

  • The binary will be in the .build/<preset-name> folder.

CMake supports different build modes, which can be further customized with individual options. By default re2c builds with -O2 -g and does not set any particular mode to allow the user complete freedom in overriding the build options. To enable a build mode at configure phase, use -DCMAKE_BUILD_TYPE=<mode> option (this works with single-config generators, such as Makefiles or Ninja). At build phase use --config <mode> option. The following modes are supported:

  • Release This is an optimized -O3 -DNDEBUG build without debug symbols, asserts and debug checks.

  • Debug This is a non-optimized -g -DRE2C_DEBUG build with debug symbols, asserts, and debug checks.

  • RelWithDebInfo This is an optimized -O2 -g -DNDEBUG build with debug symbols, but without asserts and debug checks.

  • MinSizeRel This is an optimized for size -Os -DNDEBUG build without debug symbols, asserts and debug checks.

  • Asan This is a non-optimized -g -fsanitize=address build that instruments the code with Address Sanitizer to check for memory errors.

  • Ubsan This is a non-optimized -g -fsanitize=undefined build that instruments the code with Undefined Behavior Sanitizer to check for undefined behavior errors.

A simple build (objects are generated in a separate build directory):

$ mkdir .build && cd .build && cmake .. && cmake --build .

CMake supports a lot of configuration options. Here is the list of options specific to re2c:

  • -DRE2C_BUILD_RE2GO=yes Build re2go executable (an alias to re2c --lang go). Enabled by default.

  • -DRE2C_BUILD_RE2RUST=yes Build re2rust executable (an alias to re2c --lang rust). Enabled by default.

  • -DRE2C_REBUILD_LEXERS=yes Enable regeneration of lexers from .re files (as opposed to using pre-generated bootstrap files). This requires setting -DRE2C_FOR_BUILD to an existing re2c executable path.

  • -DRE2C_REBUILD_PARSERS=yes Enable regeneration of parsers from .ypp files with bison (as opposed to using pre-generated bootstrap files).

  • -DRE2C_REBUILD_DOCS=yes Enable regeneration of documentation (requires Python 3 Docutils).

  • -DRE2C_BUILD_BENCHMARKS=yes Build benchmarks (requires Google benchmarks library).

  • -DRE2C_REGEN_BENCHMARKS=yes Regenerate C code for Ragel and Kleenex benchmarks (this will download and build Ragel and Kleenex). re2c benchmarks are always regenerated.

  • -DRE2C_BUILD_LIBS=yes Build the experimental libre2c library that provides POSIX regcomp/regexec/regfree interface to re2c.

Cross-compile re2c for Windows using Mingw:

$ cmake . -DCMAKE_TOOLCHAIN_FILE=cmake/Toolchain-cross-mingw32-linux.cmake \
    -DCMAKE_EXE_LINKER_FLAGS="-static -static-libstdc++ -static-libgcc" \
    -DBUILD_SHARED_LIBS=no

There is a bunch of build scripts for specialized builds with Asan, Ubsan, GLIBCXX_DEBUG, etc. in the build subdirectory.

Test

re2c has a main test suite and a number of unit tests. Run them all:

$ make check

Run only the main test suite and watch the progress dumped on stdout:

$ python3 run_tests.py -j<N>

Run the main test suite with --skeleton re2c option:

$ python3 run_tests.py --skeleton

Run the test suite under Valgrind (takes some time and memory):

$ python3 run_tests.py --valgrind

Test Mingw builds with Wine:

$ make wtests

Check the distribution (works with Autotools):

$ make distcheck

re2c provides a helper script build/__alltest.sh that builds and tests various re2c build flavours with Asan, Ubsan, GLIBCXX_DEBUG, etc. There is a couple of fuzz-testing Haskell scripts in the fuzz subdirectory; they are based on the QuickCheck library and can be easily modified to fuzz-test various aspects of re2c by comparing current re2c version against older versions or against other regular expression libraries.