It has many changes like:
Added a CMake-based build system.( as well as Autoconf-based system).
Improved ability to generate C++-compatible code. First, the
command-line option --lang-cpp now sets other options automatically
(--match-exact-qualifiers, --no-vol-struct-union-fields, and
--no-const-struct-union-fields). Second, the new command-line option
--cpp11 tells Csmith to generate C++11-compatible code. The default is
to generate C++03-compatible code. Thanks to Natalia Glagoleva for the
implementation of these features.
Added command-line options:
--global-variables / --no-global-variables: allow or disallow global
variables (allowed by default)
--const-struct-union-fields / --no-const-struct-union-fields: allow or
disallow const fields in structs and unions (allowed by default)
--strict-float to disallow assignments
between floats and integers. Unless this option is specified, such
assignments are allowed.
--fast-execution that biases Csmith toward
generating faster programs.
Removed --deputy command-line option, which previously caused Csmith to
output annotations for Deputy, a dependent type system for C.