Boogie

Boogie is an intermediate verification language (IVL), intended as a layer on which to build program verifiers for other languages. Several program verifiers have been built in this way, including the VCC and HAVOC verifiers for C and the verifiers for Dafny, Chalice, and Spec#. For a sample verifier for a toy language built on top of Boogie, see Forro.

Boogie is also the name of a tool. The tool accepts the Boogie language as input, optionally infers some invariants in the given Boogie program, and then generates verification conditions that are passed to an SMT solver. The default SMT solver is Z3.

Documentation

Here are some resources to learn more about Boogie. Be aware that some information might be incomplete or outdated.

• Documentation
• Language reference.
• This is Boogie 2 details many aspects of the Boogie IVL but is slightly out of date.

Getting help and contribute

You can ask questions and report issues on our issue tracker.

We are happy to receive contributions via pull requests.

Dependencies

Boogie requires .NET Core and a supported SMT solver (see below).

Installation

Boogie releases are packaged as a .NET Core global tool available at nuget.org. To install Boogie simply run:

$ dotnet tool install --global boogie

Building

To build Boogie run:

$ dotnet build Source/Boogie.sln

The compiled Boogie binary is Source/BoogieDriver/bin/${CONFIGURATION}/${FRAMEWORK}/BoogieDriver.

Backend SMT Solver

The default SMT solver for Boogie is Z3. Support for CVC5 and Yices2 is experimental.

By default, Boogie looks for an executable called z3|cvc5|yices2[.exe] in your PATH environment variable. If the solver executable is called differently on your system, use /proverOpt:PROVER_NAME=<exeName>. Alternatively, an explicit path can be given using /proverOpt:PROVER_PATH=<path>.

To learn how custom options can be supplied to the SMT solver (and more), call Boogie with /proverHelp.

Z3

The current test suite assumes version 4.8.8, but earlier and newer versions may also work.

CVC5 (experimental)

Call Boogie with /proverOpt:SOLVER=CVC5.

Yices2 (experimental)

Call Boogie with /proverOpt:SOLVER=Yices2 /useArrayTheory.

Works for unquantified fragments, e.g. arrays + arithmetic + bitvectors. Does not work for quantifiers, generalized arrays, datatypes.

Testing

Boogie has two forms of tests. Driver tests and unit tests

Driver tests

See the Driver test documentation

Unit tests

See the Unit test documentation

Versioning and Release

The current version of Boogie is noted in a build property. To push a new version to nuget, perform the following steps:

• Update the version (e.g., x.y.z) in Source/Directory.Build.props
• git add Source/Directory.Build.props; git commit -m "Release version x.y.z" to commit the change locally
• git push origin master:release-vx.y.z to push your change in a separate branch, where origin normally denotes the remote on github.com
• Create a pull request and wait for it to be approved and merged
• git tag vx.y.z to create a local tag for the version
• git push origin vx.y.z to push the tag once the pull request is merged

The CI workflow will build and push the packages.

License

Boogie is licensed under the MIT License (see LICENSE.txt).