Rust: Add variable consistency query

Author: hvitved

rust/ql/consistency-queries/VariableConsistency.ql

@@ -0,0 +1,8 @@
+/**
+ * @name Variable inconsistencies
+ * @description Lists the variable inconsistencies in the database.  This query is intended for internal use.
+ * @kind table
+ * @id rust/diagnostics/variable-consistency
+ */
+
+import codeql.rust.internal.VariableConsistency

rust/ql/lib/codeql/rust/internal/VariableConsistency.qll

@@ -0,0 +1,10 @@
+/**
+ * Provides logic for recognizing variable inconsistencies.
+ */
+
+private import rust
+
+query predicate multipleVariableTargets(VariableAccess va, Variable v1) {
+  va = v1.getAnAccess() and
+  strictcount(va.getVariable()) > 1
+}

rust/ql/test/library-tests/variables/CONSISTENCY/VariableConsistency.expected

@@ -0,0 +1,2 @@
+| main.rs:367:20:367:20 | x | main.rs:364:9:364:9 | x |
+| main.rs:367:20:367:20 | x | main.rs:366:18:366:18 | x |