From e8f38b2870965bacfff3d5339e5e5b410d40b960 Mon Sep 17 00:00:00 2001
From: Owen Mansel-Chan <owen-mc@github.com>
Date: Fri, 29 May 2026 13:34:22 +0100
Subject: [PATCH] Fix CFG for return instructions

---
 go/ql/lib/semmle/go/controlflow/ControlFlowGraphShared.qll | 5 +----
 go/ql/lib/semmle/go/controlflow/IR.qll                     | 6 ++----
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/go/ql/lib/semmle/go/controlflow/ControlFlowGraphShared.qll b/go/ql/lib/semmle/go/controlflow/ControlFlowGraphShared.qll
index b5c95dc93e8..a5c98645dff 100644
--- a/go/ql/lib/semmle/go/controlflow/ControlFlowGraphShared.qll
+++ b/go/ql/lib/semmle/go/controlflow/ControlFlowGraphShared.qll
@@ -432,9 +432,6 @@ module GoCfg {
         or
         n instanceof Go::IncDecStmt and tag = "incdec-rhs"
         or
-        // Return node
-        n instanceof Go::ReturnStmt and tag = "return"
-        or
         // Result write nodes in return statements
         exists(int i, Go::ReturnStmt ret |
           n = ret and
@@ -950,7 +947,7 @@ module GoCfg {
           n2.isAdditional(ret, tag2)
         )
         or
-        // Last return epilogue → In(ret) (the return itself)
+        // Last return epilogue → return node
         n1.isAdditional(ret, getLastReturnEpilogueTag(ret)) and
         n2.isIn(ret)
       )
diff --git a/go/ql/lib/semmle/go/controlflow/IR.qll b/go/ql/lib/semmle/go/controlflow/IR.qll
index 22300f3688b..86df852f7a5 100644
--- a/go/ql/lib/semmle/go/controlflow/IR.qll
+++ b/go/ql/lib/semmle/go/controlflow/IR.qll
@@ -893,7 +893,7 @@ module IR {
   class ReturnInstruction extends Instruction {
     ReturnStmt ret;
 
-    ReturnInstruction() { this.isAdditional(ret, "return") }
+    ReturnInstruction() { this.isIn(ret) }
 
     /** Gets the corresponding `ReturnStmt`. */
     ReturnStmt getReturnStmt() { result = ret }
@@ -938,9 +938,7 @@ module IR {
       exists(retStmt.getAnExpr())
     }
 
-    private ReturnInstruction getReturnInstruction() {
-      result.(ReturnInstruction).isAdditional(retStmt, "return")
-    }
+    private ReturnInstruction getReturnInstruction() { result.getReturnStmt() = retStmt }
 
     override Instruction getRhs() { result = this.getReturnInstruction().getResult(idx) }