The `instanceFieldStep` disjunct of `TypeTrackingInput::levelStepCall`
that was added in 7.2.0 uses `classInstanceTracker(cls)` -- which is
itself a type-tracker -- inside `levelStepCall`. That creates a
structural mutual recursion between the main type-tracker fixpoint and
`classInstanceTracker`, causing the type-tracker delta to blow up to
~100M tuples per iteration on some OOP-heavy Python codebases.
Verified on the python/mypy database: SSRF query wall time goes from
~12s before the offending commit to >40 minutes after it.
This hotfix temporarily drops the `instanceFieldStep` disjunct and
keeps only `inheritedFieldStep`, which does not pull on the call
graph and is well-behaved (verified at ~12s on mypy). The
`instanceFieldStep` helper predicate itself is kept in place, and
the `levelStepCall` body has a commented-out call to it so the
change is trivial to re-enable once the recursion issue is properly
addressed.
The previous fix required all outermost callers of a reusable workflow to
be protected, which collapsed distinct safe/unsafe inner paths that share
the same outermost caller. Track protection per caller chain instead: a
node inside a reusable workflow is only considered protected if there is
no unprotected caller path up to an outer workflow.
Adds a branching nested regression test where one inner job is protected
by a permission check and a sibling inner job is not.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adds a new defaulted signature predicates to the shared CFG library:
- getLoopElse: `else` block of a loop statement, if
any (used by Python's `while-else` / `for-else` constructs).
The predicate defaults to `none()`, so behaviour is unchanged for any
language that doesn't override it (verified by re-running
java/ql/test/library-tests/controlflow/).
The Make0 succession rules are extended:
- WhileStmt/ForeachStmt: route the loop-exit edge through the else
block before reaching the after-position.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Preparatory refactor for the shared-CFG dataflow migration. Switches
'import python' to 'import python as Py' inside Flow.qll, and qualifies
every AST-class reference (Expr, Bytes, Dict, AssignExpr, Compare,
Module, Scope, Call, Attribute, SsaVariable, AugAssign, etc.) with the
Py:: prefix.
Flow.qll's own CFG types (ControlFlowNode, BasicBlock, CallNode,
NameNode, DefinitionNode, CompareNode, ...) keep their unqualified
names — they remain the public CFG API exported from this file.
This is a semantic noop: the qualification was applied mechanically by
script and no name resolution changes. Verified by:
- All 361 lib/ + src/ queries compile clean.
- All 186 ControlFlow + PointsTo + dataflow library-tests pass.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
