Merge pull request #19483 from yoff/ruby/more-capturedExitRead

Ruby: More captured exit read nodes

Author: yoff

ruby/ql/lib/change-notes/2025-05-13-captured-variables-live-more-often.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* Captured variables are currently considered live when the capturing function exits normally. Now they are also considered live when the capturing function exits via an exception.

ruby/ql/lib/codeql/ruby/dataflow/internal/SsaImpl.qll

@@ -106,7 +106,6 @@ private predicate writesCapturedVariable(Cfg::BasicBlock bb, LocalVariable v) {
  * at index `i` in exit block `bb`.
  */
 private predicate capturedExitRead(Cfg::AnnotatedExitBasicBlock bb, int i, LocalVariable v) {
-  bb.isNormal() and
   writesCapturedVariable(bb.getAPredecessor*(), v) and
   i = bb.length()
 }

ruby/ql/test/query-tests/variables/DeadStoreOfLocal/DeadStoreOfLocal.rb

@@ -33,4 +33,34 @@ def m(y)
         y = 3  # OK - the call to `super` sees the value of `y``
         super
     end
+end
+
+def do_twice
+    yield
+    yield
+end
+    
+def get_done_twice x
+    do_twice do
+        print x
+        x += 1  # OK - the block is executed twice
+    end
+end
+
+def retry_once
+    yield
+rescue
+    yield
+end
+    
+def get_retried x
+    retry_once do
+        print x
+        if x < 1
+            begin
+                x += 1  # OK - the block may be executed again
+                raise StandardError
+            end
+        end
+    end
 end