From 63eac64da512d324f3f4a448dc9552b5b4be8c6b Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Wed, 20 Mar 2024 12:28:23 +0100
Subject: [PATCH] Fix #12512 fuzzing timeout in compileExpression() (#6160)

---
 lib/tokenlist.cpp                                            | 5 ++++-
 .../timeout-0ee5eed9abd34e9d23640a5b82dd724affd05b79         | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)
 create mode 100644 test/cli/fuzz-timeout/timeout-0ee5eed9abd34e9d23640a5b82dd724affd05b79

diff --git a/lib/tokenlist.cpp b/lib/tokenlist.cpp
index 5e9017eb487..af8d20e17d8 100644
--- a/lib/tokenlist.cpp
+++ b/lib/tokenlist.cpp
@@ -1758,7 +1758,10 @@ static Token * createAstAtToken(Token *tok)
 void TokenList::createAst() const
 {
     for (Token *tok = mTokensFrontBack.front; tok; tok = tok ? tok->next() : nullptr) {
-        tok = createAstAtToken(tok);
+        Token* const nextTok = createAstAtToken(tok);
+        if (precedes(nextTok, tok))
+            throw InternalError(tok, "Syntax Error: Infinite loop when creating AST.", InternalError::AST);
+        tok = nextTok;
     }
 }
 
diff --git a/test/cli/fuzz-timeout/timeout-0ee5eed9abd34e9d23640a5b82dd724affd05b79 b/test/cli/fuzz-timeout/timeout-0ee5eed9abd34e9d23640a5b82dd724affd05b79
new file mode 100644
index 00000000000..5f9465da55e
--- /dev/null
+++ b/test/cli/fuzz-timeout/timeout-0ee5eed9abd34e9d23640a5b82dd724affd05b79
@@ -0,0 +1 @@
+;new t()
\ No newline at end of file