From 42c07b37451377858666e8716b60c1ceef022f83 Mon Sep 17 00:00:00 2001
From: Tom Hvitved <hvitved@github.com>
Date: Thu, 20 Aug 2026 14:47:33 +0200
Subject: [PATCH 1/2] Rust: Exclude 'unused variable' results for functions
 containing `todo!()` or `unimplemented!()`

---
 rust/ql/src/queries/unusedentities/UnusedVariable.qll | 9 +++++++--
 rust/ql/test/query-tests/unusedentities/main.rs       | 8 ++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/rust/ql/src/queries/unusedentities/UnusedVariable.qll b/rust/ql/src/queries/unusedentities/UnusedVariable.qll
index 744af559dd2a..22070162d78a 100644
--- a/rust/ql/src/queries/unusedentities/UnusedVariable.qll
+++ b/rust/ql/src/queries/unusedentities/UnusedVariable.qll
@@ -1,4 +1,5 @@
 import rust
+private import codeql.rust.internal.PathResolution
 
 /**
  * A deliberately unused variable, for example `_` or `_x`.
@@ -23,9 +24,13 @@ predicate isUnused(Variable v) {
  */
 class IncompleteCallable extends Callable {
   IncompleteCallable() {
-    exists(MacroExpr me |
-      me.getEnclosingCallable() = this and
+    exists(MacroExpr me | me.getEnclosingCallable() = this |
       not me.getMacroCall().hasMacroCallExpansion()
+      or
+      exists(ItemNode i |
+        i.getCanonicalPath(_) = ["core::macros::unimplemented", "core::macros::todo"] and
+        me.getMacroCall().resolveMacro() = i
+      )
     )
   }
 }
diff --git a/rust/ql/test/query-tests/unusedentities/main.rs b/rust/ql/test/query-tests/unusedentities/main.rs
index a08a05a83bde..3f89e1d79155 100644
--- a/rust/ql/test/query-tests/unusedentities/main.rs
+++ b/rust/ql/test/query-tests/unusedentities/main.rs
@@ -558,6 +558,14 @@ trait MyTrait {
     fn my_func2(&self, x: i32) -> i32;
 }
 
+fn unimplemented(x : i32) {
+    unimplemented!()
+}
+
+fn todo(x : i32) {
+    todo!()
+}
+
 // --- main ---
 
 fn main() {

From bbff992ee161a21c59c26d6b2747a741763b715f Mon Sep 17 00:00:00 2001
From: Tom Hvitved <hvitved@github.com>
Date: Thu, 20 Aug 2026 17:18:42 +0200
Subject: [PATCH 2/2] Add change note

---
 .../2026-08-20-unused-variables-in-incomplete-functions.md    | 4 ++++
 1 file changed, 4 insertions(+)
 create mode 100644 rust/ql/src/change-notes/2026-08-20-unused-variables-in-incomplete-functions.md

diff --git a/rust/ql/src/change-notes/2026-08-20-unused-variables-in-incomplete-functions.md b/rust/ql/src/change-notes/2026-08-20-unused-variables-in-incomplete-functions.md
new file mode 100644
index 000000000000..882c91178175
--- /dev/null
+++ b/rust/ql/src/change-notes/2026-08-20-unused-variables-in-incomplete-functions.md
@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* The `rust/unused-variable` query no longer reports variables in functions containing the standard `todo!()` or `unimplemented!()` macros.
\ No newline at end of file