How to build

Dependencies

To build re2c from a release tarball one needs only a C++ compiler and optionally Python 3 to run the tests.

To develop re2c one also needs CMake or Autotools. Re2c can be built with either of the two build systems, and they are both maintained and tested on CI. Other build dependencies include Bison (to rebuild parsers), rst2man (to rebuild documentation), Sphinx (to rebuild the website), and optionally Mingw and Wine (to run Windows tests on Linux). 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 pregenerated bootstrap files. To regenerate these files it is necessary to configure re2c in a special way and provide a path to an existing re2c binary (see the details below). Normally this is not necessary, and the pregenerated files can be used as long as the .re files are unchanged.

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

  • --enable-docs Enable regeneration of documentation (requires rst2man).

  • --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)

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_REBUILD_LEXERS=yes Enable regeneration of .re files (as opposed to using bootstrap files). This requires setting -DRE2C_FOR_BUILD to an existing re2c executable path.

  • -DRE2C_REBUILD_DOCS=yes Enable regeneration of documentation (requires rst2man).

  • -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.