Member predicate DataFlow::InvokeNode::getACallee

Gets a callee of this call site where imprecision is a heuristic measure of how likely it is that callee is only suggested as a potential callee due to imprecise analysis of global variables and is not, in fact, a viable callee at all.

Callees with imprecision zero, in particular, have either been derived without considering global variables, or are calls to a global variable within the same file, or a global variable that has unique definition within the project.

This predicate can be overridden to alter the call graph used by the interprocedural data flow libraries.