diff --git a/lib/tokenlist.cpp b/lib/tokenlist.cpp
index a26d8820b..c30f9db3d 100644
--- a/lib/tokenlist.cpp
+++ b/lib/tokenlist.cpp
@@ -320,7 +320,7 @@ bool TokenList::createTokens(std::istream &code, const std::string& file0)
 
                 std::getline(code, line);
 
-                unsigned int row;
+                unsigned int row=0;
                 std::istringstream fiss(line);
                 if (fiss >> row) {
                     // Update the current line number
@@ -955,6 +955,7 @@ static Token * createAstAtToken(Token *tok, bool cpp)
                 ;
             else if (Token::simpleMatch(tok->astParent(), "(") &&
                      Token::simpleMatch(tok->astParent()->astParent(), "[") &&
+                     tok->astParent()->astParent()->astOperand1() &&
                      tok == tok->astParent()->astParent()->astOperand1()->astOperand1())
                 ;
             else
diff --git a/test/testgarbage.cpp b/test/testgarbage.cpp
index 444286f94..cb433a683 100644
--- a/test/testgarbage.cpp
+++ b/test/testgarbage.cpp
@@ -130,6 +130,7 @@ private:
         TEST_CASE(garbageCode88);
         TEST_CASE(garbageCode89);
         TEST_CASE(garbageCode90);
+        TEST_CASE(garbageCode91);
 
         TEST_CASE(garbageValueFlow);
         TEST_CASE(garbageSymbolDatabase);
@@ -712,6 +713,10 @@ private:
         ASSERT_THROW(checkCode("{ } { } typedef int u_array [[ ] ; typedef u_array & u_array_ref] ( ) { } u_array_ref_gbl_obj0"), InternalError); // do not crash
     }
 
+    void garbageCode91() { // #6791
+        checkCode("typedef __attribute__((vector_size (16))) { return[ (v2df){ } ;] }"); // do not crash
+    }
+
     void garbageValueFlow() {
         // #6089
         const char* code = "{} int foo(struct, x1, struct x2, x3, int, x5, x6, x7)\n"