Rust: Use macro call location as fall back in macro expansions

Author: hvitved

rust/ql/lib/codeql/rust/elements/internal/LocatableImpl.qll

@@ -46,11 +46,25 @@ module Impl {
     predicate fromSource() { exists(this.getFile().getRelativePath()) }
   }
 
+  private @location_default getDbLocation(Locatable l) {
+    locatable_locations(Synth::convertLocatableToRaw(l), result)
+  }
+
+  private MacroCall getImmediatelyEnclosingMacroCall(AstNode n) {
+    result = n.getParentNode()
+    or
+    exists(AstNode mid |
+      result = getImmediatelyEnclosingMacroCall(mid) and
+      n.getParentNode() = mid and
+      not mid instanceof MacroCall
+    )
+  }
+
   /** Gets the non-synthesized location of `l`, if any. */
   LocationImpl::LocationDefault getLocationDefault(Locatable l) {
-    exists(@location_default location |
-      result = LocationImpl::TLocationDefault(location) and
-      locatable_locations(Synth::convertLocatableToRaw(l), location)
-    )
+    result = LocationImpl::TLocationDefault(getDbLocation(l))
+    or
+    not exists(getDbLocation(l)) and
+    result = getLocationDefault(getImmediatelyEnclosingMacroCall(l))
   }
 }

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

@@ -25,7 +25,8 @@ query predicate multipleLocations(Locatable e) { strictcount(e.getLocation()) >
  * Holds if `e` does not have a `Location`.
  */
 query predicate noLocation(Locatable e) {
-  not exists(e.getLocation()) and not e.(AstNode).getParentNode*() = any(Crate c).getModule()
+  not exists(e.getLocation()) and
+  not e.(AstNode).getParentNode*() = any(Crate c).getModule()
 }
 
 private predicate multiplePrimaryQlClasses(Element e) {