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Fault can be built for source if you like, but the best way to install Fault is by downloading the correct release for your machine.

Once installed the model checker of Fault needs access to a SMT solver, otherwise Fault will default to generating SMT of models only. Microsoft’s Z3 is the recommended solver at this time and can be downloaded here

Then in order for Fault to find your solver you need to set two configuration variables

export SOLVERCMD="z3"
export SOLVERARG="-in"

SOLVERCMD is the command for the solver. SOLVERARG is whatever argument the the solver takes to read SMT from Stdin.

That’s it! You should be able to run Fault now

> fault -f=../path/to/my/model.fsystem
  Fault found the following scenario

Fault Command Line

Flag Meaning Options
-f Required path to the .fsystem or .fspec file  
-m Mode to run Fault in. This determines what Fault outputs and allows you to do things like stop the compiler and have it return just the SMT - ast Returns Fault AST
- ir Returns LLVM IR representation of the model
- smt Returns the generated SMT
- check (default) Returns solution from the solver.
-i Input format. Allows you to start the compiler from a midpoint by inputting LLVM IR or SMT. Useful in debugging - fspec (default) Fault files fspec/fsystem
-smt2 SMT-Lib2 formatted rules.
-format How to display the output returned by the solver -log Event log style format
-static Variable are assumed to be static rules with no feedback loops
-smt No format or filtering, passes the results from the solver directly
-legacy State changes organized by variable.
- visualize Returns solution from the solver formatted in Mermaid.js visualizations.
-c Completeness. This runs a reachability check on the state chart before compiling the model. Makes sure that there are no states that are defined but unreachable under any conditions. true or false

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