diff --git a/CMakeLists.txt b/CMakeLists.txt
index 049a0358..47fcc94c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.0)
 
 project(s3select)
 
-set(CMAKE_CXX_FLAGS "-std=gnu++17 -ggdb -Wnon-virtual-dtor -Wreorder -Wunused-variable")
+set(CMAKE_CXX_FLAGS "-std=gnu++17 -ggdb -Wnon-virtual-dtor -Wreorder -Wunused-variable -Wmaybe-uninitialized")
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
diff --git a/include/s3select_functions.h b/include/s3select_functions.h
index 6849de96..24c412be 100644
--- a/include/s3select_functions.h
+++ b/include/s3select_functions.h
@@ -556,42 +556,44 @@ struct _fn_max : public base_function
 
 struct _fn_to_int : public base_function
 {
-
   value var_result;
-  value func_arg;
 
   bool operator()(bs_stmt_vec_t* args, variable* result) override
   {
-    char* perr;
-    int64_t i=0;
-    func_arg = (*args->begin())->eval();
+    value v = (*args->begin())->eval();
 
-    if (func_arg.type == value::value_En_t::STRING)
+    switch (v.type) {
+
+    case value::value_En_t::STRING:
     {
+      char* pend;
       errno = 0;
-      i = strtol(func_arg.str(), &perr, 10) ;  //TODO check error before constructor
-      if ((errno == ERANGE && (i == LONG_MAX || i == LONG_MIN)) || (errno != 0 && i == 0)) {
+      int64_t i= strtol(v.str(), &pend, 10);
+      if (errno == ERANGE) {
         throw base_s3select_exception("converted value would fall out of the range of the result type!");
-        return false;   
-    }
-    
-    if (*perr != '\0') {
-      throw base_s3select_exception("characters after int!");
-      return false;
-    }
-  } 
-    else if (func_arg.type == value::value_En_t::FLOAT)
-    {
-      i = func_arg.dbl();
-    }
-    else
-    {
-      i = func_arg.i64();
+      }
+      if (pend == v.str()) {
+        // no number found
+        throw base_s3select_exception("text cannot be converted to a number");
+      }
+      if (*pend) {
+        throw base_s3select_exception("extra characters after the number");
+      }
+
+      var_result = i;
     }
+    break;
 
-    var_result =  i ;
-    *result =  var_result;
+    case value::value_En_t::FLOAT:
+      var_result = static_cast<int64_t>(v.dbl());
+      break;
 
+    default:
+      var_result = v.i64();
+      break;
+    }
+
+    *result = var_result;
     return true;
   }
 
diff --git a/test/s3select_test.cpp b/test/s3select_test.cpp
index 66f33eb9..a09731a9 100644
--- a/test/s3select_test.cpp
+++ b/test/s3select_test.cpp
@@ -3444,6 +3444,14 @@ TEST(TestS3selectFunctions, floatcast)
   test_single_column_single_row("select cast('999e+999' as float) from s3object;","#failure#","converted value would fall out of the range of the result type!");
 }
 
+TEST(TestS3selectFunctions, intcast)
+{
+  test_single_column_single_row("select cast('1234a' as int) from s3object;","#failure#","extra characters after the number");
+  test_single_column_single_row("select cast('a1234' as int) from s3object;","#failure#","text cannot be converted to a number");
+  test_single_column_single_row("select cast('9223372036854775808' as int) from s3object;","#failure#","converted value would fall out of the range of the result type!");
+  test_single_column_single_row("select cast('-9223372036854775809' as int) from s3object;","#failure#","converted value would fall out of the range of the result type!");
+}
+
 TEST(TestS3selectFunctions, predicate_as_projection_column)
 {
   std::string input;