diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index d58ec03ec..c639bf27d 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -541,7 +541,8 @@ Token *Tokenizer::processFunc(Token *tok2, bool inOperator) const
                     return nullptr;
 
                 if (tok2->str() == "(" &&
-                    tok2->link()->next()->str() == "(") {
+                    tok2->link()->next() &&
+					tok2->link()->next()->str() == "(") {
                     tok2 = tok2->link();
 
                     if (tok2->next()->str() == "(")
diff --git a/test/testgarbage.cpp b/test/testgarbage.cpp
index 39b6f4dc6..5a1dc4fdf 100644
--- a/test/testgarbage.cpp
+++ b/test/testgarbage.cpp
@@ -117,6 +117,7 @@ private:
         TEST_CASE(garbageCode76);
 		TEST_CASE(garbageCode77);
 		TEST_CASE(garbageCode78);
+		TEST_CASE(garbageCode79);
 
         TEST_CASE(garbageValueFlow);
         TEST_CASE(garbageSymbolDatabase);
@@ -650,6 +651,10 @@ private:
         checkCode("( ) { [ ] } ( ) { } const_array_of_int ( ) { } typedef int A [ ] [ ] ; A a = { { } { } }");
     }
 
+	void garbageCode79() { // #6757
+        ASSERT_THROW(checkCode("{ } { } typedef void ( func_type ) ( ) ; func_type & ( )"), InternalError);
+    }
+
     void garbageValueFlow() {
         // #6089
         const char* code = "{} int foo(struct, x1, struct x2, x3, int, x5, x6, x7)\n"