Fixed #2120 (False positive: array index out of bounds (unknown type in struct, sub function))

lib/checkbufferoverrun.cpp

@@ -1804,7 +1804,7 @@ bool CheckBufferOverrun::ArrayInfo::declare(const Token *tok, const Tokenizer &t
     _element_size = 0;
     _varname.clear();
 
-    if (!tok->isName())
+    if (!tok->isName() || tok->str() == "return")
         return false;
 
     while (tok && (tok->str() == "static" ||

test/testbufferoverrun.cpp

@@ -180,6 +180,7 @@ private:
 
         TEST_CASE(executionPaths1);
         TEST_CASE(executionPaths2);
+        TEST_CASE(executionPaths3);   // no FP for function parameter
 
         TEST_CASE(cmdLineArgs1);
 
@@ -2514,6 +2515,20 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void executionPaths3()
+    {
+        epcheck("void f(char *VLtext)\n"
+                "{\n"
+                "    if ( x ) {\n"
+                "        return VLtext[0];\n"
+                "    } else {\n"
+                "        int wordlen = ab();\n"
+                "        VLtext[wordlen] = 0;\n"
+                "    }\n"
+                "}\n");
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void cmdLineArgs1()
     {
         check("int main(int argc, char* argv[])\n"