mirror of
https://github.com/github/codeql.git
synced 2026-03-24 00:16:49 +01:00
3fafb47b16
A slightly odd fix, but still morally okay, I think. The main issue here was that global variables have their first occurrence in an inner scope inside a so-called "scope entry definition", that then subsequently flows to the first use of this variable. This meant that that first use was _not_ a `LocalSourceNode` (since _something_ flowed into it), and this blocked `trackUseNode` from type-tracking to it (as it expects all nodes to be `LocalSourceNode`s). The answer, then, is to say that a `LocalSourceNode` is simply one that doesn't have flow to it from _any `CfgNode`_ (through one or more steps). This disregards the flow from the scope entry definition, as that is flow from an `EssaNode`. Additionally, it makes sense to exclude `ModuleVariableNode`s. These should never be considered local sources, since they always have flow from (at least) the place where the corresponding global variable is introduced.