zig lang

A system programming language intended to replace C.

Zig intends to remain a small language, yet powerful enough to write optimal, readable, safe, and concise code to solve any computing problem.

Porting a C project to Zig should be a pleasant experience - every C feature needs a corresponding Zig feature which solves the problem equivalently or better.

Zig is not afraid to roll the major version number of the language if it improves simplicity, fixes poor design decisions, or adds a new feature which compromises backward compatibility.

Introduction to the Zig Programming Language

Existing Features

• Compatible with C libraries with no wrapper necessary. Directly include C .h files and get access to the functions and symbols therein.
• Compile units do not depend on libc unless explicitly linked.
• Provides standard library which competes with the C standard library and is always compiled against statically in source form.
• Pointer types do not allow the null value. Instead you can use a maybe type which has several syntactic constructs to ensure that the null pointer is not missed.
• Provides an error type with several syntatic constructs which makes writing robust code convenient and straightforward. Writing correct code is easier than writing buggy code.
• No header files required. Top level declarations are entirely order-independent.
• Powerful constant expression evaluator. Generally, anything that can be figured out at compile time is figured out at compile time.
• Tagged union enum type. No more accidentally reading the wrong union field.
• Easy to parse language so that humans and machines have no trouble with the syntax.
• The binaries produced by Zig have complete debugging information so you can, for example, use GDB to debug your software.
• Debug mode optimizes for fast compilation time and crashing when undefined behavior would happen.
• Release mode produces heavily optimized code. What other projects call "Link Time Optimization" Zig does automatically.
• Mark functions as tests and automatically run them with zig test.
• Supported architectures: x86_64, i386
• Supported operating systems: linux
• Friendly toward package maintainers. Reproducible build, bootstrapping process carefully documented. Issues filed by package maintainers are considered especially important.
• Easy cross-compiling.
• Eliminate the preprocessor, but (most) everything you can accomplish with the preprocessor, you can accomplish directly in the language.

Planned Features

• In addition to creating executables, creating a C library is a primary use case. You can export an auto-generated .h file.
• Generics so that one can write efficient data structures that work for any data type.
• Eliminate the need for configure, make, cmake, etc.
• Automatically provide test coverage.
• Ability to declare dependencies as Git URLS with commit locking (can provide a tag or sha256).
• Include documentation generator.
• Compiler exposes itself as a library.
• Support for all popular architectures and operating systems.

Building

Dependencies

• cmake >= 2.8.5
• LLVM == 3.8.0
• libclang == 3.8.0

Debug / Development Build

If you have gcc or clang installed, you can find out what ZIG_LIBC_LIB_DIR and ZIG_LIBC_STATIC_LIB_DIR should be set to (example below). ZIG_LIBC_INCLUDE_DIR likely can be set to /usr/include.

mkdir build
cd build
cmake .. -DCMAKE_INSTALL_PREFIX=$(pwd) -DZIG_LIBC_LIB_DIR=$(dirname $(cc -print-file-name=crt1.o)) -DZIG_LIBC_INCLUDE_DIR=/usr/include -DZIG_LIBC_STATIC_LIB_DIR=$(dirname $(cc -print-file-name=crtbegin.o))
make
make install
./run_tests

Release / Install Build

Once installed, ZIG_LIBC_LIB_DIR and ZIG_LIBC_INCLUDE_DIR can be overridden by the --libc-lib-dir and --libc-include-dir parameters to the zig binary.

mkdir build
cd build
cmake .. -DCMAKE_BUILD_TYPE=Release -DZIG_LIBC_LIB_DIR=/some/path -DZIG_LIBC_INCLUDE_DIR=/some/path -DZIG_LIBC_STATIC_INCLUDE_DIR=/some/path
make
sudo make install

Test Coverage

To see test coverage in Zig, configure with -DZIG_TEST_COVERAGE=ON as an additional parameter to the Debug build.

You must have lcov installed and available.

Then make coverage.

With GCC you will get a nice HTML view of the coverage data. With clang, the last step will fail, but you can execute llvm-cov gcov $(find CMakeFiles/ -name "*.gcda") and then inspect the produced .gcov files.

Troubleshooting

If you get one of these:

undefined reference to `_ZNK4llvm17SubtargetFeatures9getStringB5cxx11Ev'
undefined reference to `llvm::SubtargetFeatures::getString() const'

This is because of C++'s Dual ABI. Most likely LLVM was compiled with one compiler while Zig was compiled with a different one, for example GCC vs clang.

To fix this, you have 2 options:

• Compile Zig with the same compiler that LLVM was compiled with.
• Add -DZIG_LLVM_OLD_CXX_ABI=yes to the cmake configure line.

Community

• IRC chat: #zig on Freenode.
• Reddit: /r/zig