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Nullness

Module Nullness

Provides classes and predicates for working with null values and checks for nullness.


                                import semmle.code.cpp.controlflow.Nullness

DefinitionsAndUses	Provides classes and predicates for reasoning about definitions and uses of variables.
cpp	Provides classes and predicates for working with C/C++ code.

callMayReturnNull	Holds if `call` may, directly or indirectly, evaluate to a null literal.
checkedNull	Holds if `var` is likely to be null at `node`.
checkedValid	Holds if `var` is likely to be non-null at `node`.
mayReturnNull	Holds if `f` may, directly or indirectly, return a null literal.
nullCheckExpr	Holds if `var` is null when `checkExpr` evaluates to a true value.
nullInit	Holds if the evaluation of `n` may have the effect of, directly or indirectly, assigning a null literal to `var`.
nullValue	Holds if `val` is a null literal or a call to a function that may return a null literal.
validCheckExpr	Holds if `var` is non-null when `checkExpr` evaluates to a true value.

AnalysedExpr	An expression that has been extended with member predicates that provide information about the role of this expression in nullness checks.
NullValue	A C/C++ literal whose value is considered null.
Zero	A C/C++ literal whose value is zero.