Building with CMake - Z3 Theorem Prover

CMake is the recommended build system for Z3 on most platforms. It’s a “meta build system” that generates platform-specific build files from CMakeLists.txt configuration files.

CMake is recommended for most build tasks, except for building OCaml bindings which should use the Make-based system.

Prerequisites

CMake 3.16 or later
C++20 compatible compiler (GCC, Clang, or MSVC)
Python (required for build configuration)
Git (optional, for version information)

Quick Start

Create build directory

Create a separate build directory outside the source tree:

mkdir build
cd build

CMake enforces out-of-source builds. You cannot build directly in the source directory.

Configure the build

Run CMake to configure the project:

cmake -G "Unix Makefiles" ../

For a Release build:

cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Release ../

Build Z3

Build the project using make:

make -j4  # Replace 4 with number of CPU cores

Install (optional)

Install Z3 system-wide:

sudo make install

Build Generators

CMake supports multiple generators. Choose based on your platform and preference:

Unix Makefiles

Default on most Linux/Unix systems:

cmake -G "Unix Makefiles" ../
make -j4

This is a single-configuration generator - you set the build type (Debug/Release) when running cmake.

Ninja

Ninja is significantly faster than Make due to non-recursive builds:

cmake -G "Ninja" ../
ninja

Ninja runs in parallel by default. Use the -j flag to control parallelism.

Ninja also works on Windows - just run cmake in the Visual Studio Developer Command Prompt.

Visual Studio

See the Visual Studio build guide for detailed instructions.

Build Types

CMake supports several build types:

Release - Optimized build with no debug symbols
Debug - Debug build with symbols, tracing enabled
RelWithDebInfo - Optimized build with debug symbols
MinSizeRel - Optimized for size

For single-configuration generators (Unix Makefiles, Ninja):

cmake -DCMAKE_BUILD_TYPE=Release ../

For multi-configuration generators (Visual Studio), select the build type in the IDE.

Compiler Selection

Set the compiler using environment variables on the first cmake invocation:

CC=clang CXX=clang++ cmake ../

Once configured, the compiler is fixed. To change compilers, create a new build directory or delete the contents of the current one.

Cross-compilation

For 32-bit builds on 64-bit systems with multilib GCC:

CFLAGS="-m32" CXXFLAGS="-m32" CC=gcc CXX=g++ cmake ../

CMake Configuration Options

Core Build Options

# Build shared library instead of static
cmake -DZ3_BUILD_LIBZ3_SHARED=ON ../

# Set installation prefix
cmake -DCMAKE_INSTALL_PREFIX=/usr/local ../

# Use GNU Multiple Precision library
cmake -DZ3_USE_LIB_GMP=ON ../

# Enable link-time optimization
cmake -DZ3_LINK_TIME_OPTIMIZATION=ON ../

Language Bindings

Enable various language bindings:

# Python bindings
cmake -DZ3_BUILD_PYTHON_BINDINGS=ON ../

# Java bindings
cmake -DZ3_BUILD_JAVA_BINDINGS=ON ../

# .NET bindings
cmake -DZ3_BUILD_DOTNET_BINDINGS=ON ../

# Go bindings (requires Go 1.20+ and shared library)
cmake -DZ3_BUILD_GO_BINDINGS=ON -DZ3_BUILD_LIBZ3_SHARED=ON ../

Security Features (MSVC)

When building with Visual Studio/MSVC, Control Flow Guard is enabled by default:

# Disable Control Flow Guard if needed
cmake -DZ3_ENABLE_CFG=OFF ../

See Visual Studio build guide for details on security features.

Advanced Options

# Enable tracing in non-debug builds
cmake -DZ3_ENABLE_TRACING_FOR_NON_DEBUG=ON ../

# Include git hash in version
cmake -DZ3_INCLUDE_GIT_HASH=ON ../

# Build with address sanitizer
cmake -DZ3_ADDRESS_SANITIZE=ON ../

# Single-threaded build
cmake -DZ3_SINGLE_THREADED=ON ../

Installation

Standard Installation

make install

By default, Z3 installs to:

Binaries: ${CMAKE_INSTALL_PREFIX}/bin
Libraries: ${CMAKE_INSTALL_PREFIX}/lib
Headers: ${CMAKE_INSTALL_PREFIX}/include

Custom Installation Paths

cmake -DCMAKE_INSTALL_PREFIX=/opt/z3 \
      -DCMAKE_INSTALL_BINDIR=bin \
      -DCMAKE_INSTALL_LIBDIR=lib \
      -DCMAKE_INSTALL_INCLUDEDIR=include ../

Staged Installation

For packaging, use DESTDIR:

make install DESTDIR=/path/to/staging

Uninstall

make uninstall

Using Z3 in CMake Projects

With FetchContent

Fetch Z3 directly from the repository:

include(FetchContent)
FetchContent_Declare(Z3
    GIT_REPOSITORY https://github.com/Z3Prover/z3
    GIT_TAG        z3-4.15.3
)
FetchContent_MakeAvailable(Z3)

# Add C++ API include directory
if(TARGET libz3)
    target_include_directories(libz3 INTERFACE
        $<BUILD_INTERFACE:${z3_SOURCE_DIR}/src/api/c++>
    )
endif()

target_link_libraries(yourTarget PRIVATE libz3)

With find_package

Use system-installed Z3:

find_package(Z3 4.15.3 REQUIRED CONFIG)
target_link_libraries(yourTarget PRIVATE z3::libz3)

With Fallback

Try system installation first, fall back to FetchContent:

set(Z3_MIN_VERSION "4.15.3")
find_package(Z3 ${Z3_MIN_VERSION} CONFIG QUIET)

if(Z3_FOUND)
    message(STATUS "Found system Z3 version ${Z3_VERSION_STRING}")
else()
    message(STATUS "Fetching Z3 ${Z3_MIN_VERSION}")
    include(FetchContent)
    FetchContent_Declare(Z3
        GIT_REPOSITORY https://github.com/Z3Prover/z3
        GIT_TAG        z3-${Z3_MIN_VERSION}
    )
    FetchContent_MakeAvailable(Z3)
    
    if(TARGET libz3)
        target_include_directories(libz3 INTERFACE
            $<BUILD_INTERFACE:${z3_SOURCE_DIR}/src/api/c++>
        )
    endif()
    
    if(NOT TARGET z3::libz3)
        add_library(z3::libz3 ALIAS libz3)
    endif()
endif()

target_link_libraries(yourTarget PRIVATE z3::libz3)

Building Python Bindings

With libz3

Build both library and bindings:

cmake -DZ3_BUILD_PYTHON_BINDINGS=ON -DZ3_BUILD_LIBZ3_SHARED=ON ../
make
make install

Python-only (using pre-installed libz3)

For package managers building for multiple Python versions:

# Build libz3 once
mkdir build-libz3
cd build-libz3
cmake -DZ3_BUILD_LIBZ3_SHARED=ON -DCMAKE_INSTALL_PREFIX=/usr/local ../
make install

# Build Python bindings for each version
cd ..
mkdir build-py310
cd build-py310
cmake -DZ3_BUILD_LIBZ3_CORE=OFF \
      -DZ3_BUILD_PYTHON_BINDINGS=ON \
      -DPython3_EXECUTABLE=/usr/bin/python3.10 ../
make install

Cleaning Source Tree

If you’ve previously used the Python build system, clean generated files:

# Preview files to be removed
git clean -nx src

# Remove generated files
git clean -fx src

Be careful with git clean -fx - it permanently deletes untracked files.

Developer Tools

Verbose Build Output

With Unix Makefiles:

make VERBOSE=1

With Ninja:

ninja -v

List Available Targets

make help

Special Targets

clean - Remove built files
edit_cache - Edit CMake configuration
rebuild_cache - Re-run CMake
api_docs - Build API documentation (if Z3_BUILD_DOCUMENTATION=ON)

Common Issues

Polluted Source Tree

If CMake reports a polluted source tree, you have generated files from the Python build system:

git clean -fx src

Changing Compiler

To change compilers, either:

Create a new build directory, or
Delete contents of current build directory

Then run cmake with new compiler environment variables.

Java Bindings Not Found

Set JAVA_HOME when configuring:

JAVA_HOME=/usr/lib/jvm/default cmake -DZ3_BUILD_JAVA_BINDINGS=ON ../

Next Steps

Learn about building with Make for simple Unix/Linux builds
See Visual Studio builds for Windows development
Explore Bazel builds for advanced build orchestration

Getting Started

Core Concepts

Building Z3

Guides

​Prerequisites

​Quick Start

​Build Generators

​Unix Makefiles

​Ninja

​Visual Studio

​Build Types

​Compiler Selection

​Cross-compilation

​CMake Configuration Options

​Core Build Options

​Language Bindings

​Security Features (MSVC)

​Advanced Options

​Installation

​Standard Installation

​Custom Installation Paths

​Staged Installation

​Uninstall

​Using Z3 in CMake Projects

​With FetchContent

​With find_package

​With Fallback

​Building Python Bindings

​With libz3

​Python-only (using pre-installed libz3)

​Cleaning Source Tree

​Developer Tools

​Verbose Build Output

​List Available Targets

​Special Targets

​Common Issues

​Polluted Source Tree

​Changing Compiler

​Java Bindings Not Found

​Next Steps

Build docs developers (and LLMs) love

Prerequisites

Quick Start

Build Generators

Unix Makefiles

Ninja

Visual Studio

Build Types

Compiler Selection

Cross-compilation

CMake Configuration Options

Core Build Options

Language Bindings

Security Features (MSVC)

Advanced Options

Installation

Standard Installation

Custom Installation Paths

Staged Installation

Uninstall

Using Z3 in CMake Projects

With FetchContent

With find_package

With Fallback

Building Python Bindings

With libz3

Python-only (using pre-installed libz3)

Cleaning Source Tree

Developer Tools

Verbose Build Output

List Available Targets

Special Targets

Common Issues

Polluted Source Tree

Changing Compiler

Java Bindings Not Found

Next Steps