2.8 KiB
2.7.0 (April 30, 2019)
New features
-
Added syntax for record updates (see #399 for details of implemented and planned features).
-
Updated the
:browse
command to list module parameters (issue #586). -
Added support for test vector creation (the
:dumptests
command). This feature computes a list of random inputs and outputs for the given expression of function type and saves it to a file. This is useful for generating tests from a trusted Cryptol specification to apply to an implementation written in another language.
Breaking changes
-
Removed the
[x..]
construct from the language (issue #574). It was shorthand for[x..2^^n-1]
for a bit vector of sizen
, which was often not what the user intended. Users should instead write either[x..y]
or[x...]
, to construct a smaller range or a lazy sequence, respectively. -
Renamed the value-level
width
function tolength
, and generalized its type (issue #550). It does not behave identically to the type-levelwidth
operator, which led to confusion. The namelength
matches more closely with similar functions in other languages.
Bug fixes
-
Improved type checking performance of decimal literals.
-
Improved type checking of
/^
and%^
(issues #581, #582). -
Improved performance of sequence updates with the
update
primitive (issue #579). -
Fixed elapsed time printed by
:prove
and:sat
(issue #572). -
Fixed SMT-Lib formulas generated for right shifts (issue #566).
-
Fixed crash when importing non-parameterized modules with the backtick prefix (issue #565).
-
Improved performance of symbolic execution for
Z n
(issue #554). -
Fixed interpretation of the
satNum
option so finding multiple solutions doesn't run forever (issue #553). -
Improved type checking of the
length
function (issue #548). -
Improved error message when trying to prove properties in parameterized modules (issue #545).
-
Stopped warning about defaulting at the REPL when
warnDefaulting
is set tofalse
(issue #543). -
Fixed builds on non-x86 architectures (issue #542).
-
Made browsing of interactively-bound identifiers work better (issue #538).
-
Fixed a bug that allowed changing the semantics of the
_ # _
pattern and the-
and~
operators by creating local definitions of functions that they expand to (issue #568). -
Closed issues #498, #547, #551, #562, and #563.
Solver versions
Cryptol can interact with a variety of external SMT solvers to
support the :prove
and :sat
commands, and requires Z3 for its
type checker. Many versions of these solvers will work correctly, but
for Yices and Z3 we recommend the following specific versions.
- Z3 4.7.1
- Yices 2.6.1
For Yices, this is the latest version at the time of this writing. For Z3, it is not, and the latest versions (4.8.x) include changes that cause some examples that previously succeeded to time out when type checking.