Messages

The checker

What the checker says about a circuit, and what to do about it. X stands for a block, as the message names it (AND gate "and1").

Errors

Message	What to do
X has n of its m inputs wired (input "p" is free)	Wire the free input. A library block's optional pins may stay free.
X: input "p" has n drivers	An input takes one wire: delete the others.
combinational loop: a → b → … (break it with a Unit delay)	A value is computed from itself in the same step: put a Unit delay in the loop.
X: input "p" is t, but a logic gate takes booleans	Compare the number with something first, or use an arithmetic block.
X: its inputs are t1 and t2; they must be of one type	Change the type of an In block or a constant, or cast one operand.
X: its inputs are booleans, but it takes numbers	Use a logic gate, or feed it numbers.
X: its condition is t, but must be a boolean	A Switch's if takes a boolean: compare first.
X: it switches between a t1 and a t2; they must be of one type	Make then and else of one type.
X: it checks a t, but an assertion takes a boolean	A property's input is a condition: compare first.
X: its initial value is t, but it holds a t′	A Unit delay's init and next are of its type.
X: input "p" is t, but it takes a t′	Feed the library block's pin the type it takes.
X: unknown type, operator or library block	The file was written by a newer editor or intrepyd, or by hand: update, or fix the file.
X: a constant that does not fit its type	Use a wider type, or a smaller value.
a block has no name; the name "n" is used by k blocks	Give each block a name, unique in its level.
a wire from X to Y crosses the border of a subsystem	Wire through the subsystem's In and Out blocks.

Warnings

Message	What to do
the result of X is not used	Wire it, or delete the block.
the circuit has no output and nothing to verify	Add an Out, an Assertion or a Target.

Verify and MC/DC tests

What you see	What it means
unknown	No engine answered within the timeout or the max depth. Try a longer timeout, another engine, or no depth.
a condition's pair unreachable	The condition never decides the outcome alone: it is masked, or the logic is redundant.
a condition's pair not found	No pair within the longest test and the timeout: try longer ones.
out of date	The circuit, or its decisions, changed since the results were made: run again.
the engines need a license	No valid license: see The engines' license.
a feature needs a newer intrepyd	The intrepyd in use is too old for the circuit (subsystems, optional pins, certificates, tests of formulas with next): pip install -U intrepyd.

Formulas

The check of a requirement's formula says where it is wrong: expected …, found …, unexpected …, the formula ends too early, comparisons do not chain, the steps of pre are a whole number from 1 to 100, the steps of next are a whole number from 1 to 10. The formula language has the rules.