From a5e24569a6eae5b13184ea50edfbbfb75b38dbad Mon Sep 17 00:00:00 2001
From: chrchr-github <78114321+chrchr-github@users.noreply.github.com>
Date: Sat, 15 Jun 2024 17:36:54 +0200
Subject: [PATCH] Fix #12803 fuzzing crash in Tokenizer::setVarIdPass2()
 (#6530)

---
 lib/tokenize.cpp                                                | 2 ++
 .../fuzz-crash_c/crash-7af21bec1d9be105742fdcb336514aae26ab4425 | 2 ++
 2 files changed, 4 insertions(+)
 create mode 100644 test/cli/fuzz-crash_c/crash-7af21bec1d9be105742fdcb336514aae26ab4425

diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 195924e7191..bc5d1c7443f 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -5107,6 +5107,8 @@ void Tokenizer::setVarIdPass2()
                 classnameTokens.push_back(tokStart->next());
                 tokStart = tokStart->tokAt(2);
             }
+            if (!tokStart)
+                syntaxError(tok);
         }
 
         std::string classname;
diff --git a/test/cli/fuzz-crash_c/crash-7af21bec1d9be105742fdcb336514aae26ab4425 b/test/cli/fuzz-crash_c/crash-7af21bec1d9be105742fdcb336514aae26ab4425
new file mode 100644
index 00000000000..6620c0d315f
--- /dev/null
+++ b/test/cli/fuzz-crash_c/crash-7af21bec1d9be105742fdcb336514aae26ab4425
@@ -0,0 +1,2 @@
+i
+class q::_
\ No newline at end of file