From 95681bfad48b508fafec3e3f96ae52287e567dd2 Mon Sep 17 00:00:00 2001
From: Geoffrey White <40627776+geoffw0@users.noreply.github.com>
Date: Mon, 9 Mar 2026 15:06:20 +0000
Subject: [PATCH 1/2] Rust: Fix performance issue with File.fromSource.

---
 rust/ql/lib/codeql/files/FileSystem.qll | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/rust/ql/lib/codeql/files/FileSystem.qll b/rust/ql/lib/codeql/files/FileSystem.qll
index cfab33b9a440..367f088504b4 100644
--- a/rust/ql/lib/codeql/files/FileSystem.qll
+++ b/rust/ql/lib/codeql/files/FileSystem.qll
@@ -45,13 +45,16 @@ extensible predicate additionalExternalFile(string relativePath);
 
 /** A file. */
 class File extends Container, Impl::File {
+  pragma[nomagic]
+  private string getRelativePath0() { result = this.getRelativePath() }
+
   /**
    * Holds if this file was extracted from the source code of the target project
    * (rather than another location such as inside a dependency).
    */
   predicate fromSource() {
     exists(ExtractorStep s | s.getAction() = "Extract" and s.getFile() = this) and
-    not additionalExternalFile(this.getRelativePath())
+    not additionalExternalFile(this.getRelativePath0())
   }
 
   /**

From e72c1166640ddddfae86897cf24443da0dc90dd7 Mon Sep 17 00:00:00 2001
From: Geoffrey White <40627776+geoffw0@users.noreply.github.com>
Date: Thu, 9 Apr 2026 11:18:25 +0100
Subject: [PATCH 2/2] Rust: Proposed improved solution.

---
 rust/ql/lib/codeql/files/FileSystem.qll | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/rust/ql/lib/codeql/files/FileSystem.qll b/rust/ql/lib/codeql/files/FileSystem.qll
index 367f088504b4..93ff7be604e0 100644
--- a/rust/ql/lib/codeql/files/FileSystem.qll
+++ b/rust/ql/lib/codeql/files/FileSystem.qll
@@ -46,7 +46,7 @@ extensible predicate additionalExternalFile(string relativePath);
 /** A file. */
 class File extends Container, Impl::File {
   pragma[nomagic]
-  private string getRelativePath0() { result = this.getRelativePath() }
+  private predicate isAdditionalExternalFile() { additionalExternalFile(this.getRelativePath()) }
 
   /**
    * Holds if this file was extracted from the source code of the target project
@@ -54,7 +54,7 @@ class File extends Container, Impl::File {
    */
   predicate fromSource() {
     exists(ExtractorStep s | s.getAction() = "Extract" and s.getFile() = this) and
-    not additionalExternalFile(this.getRelativePath0())
+    not this.isAdditionalExternalFile()
   }
 
   /**