Additional 5.0 fix for

Bug#15098: CAST(column double TO signed int), wrong result
which was fixed originally in 4.1.

mysql-test/r/cast.result

@@ -344,6 +344,9 @@ SELECT f1 AS double_val, CAST(f1 AS SIGNED INT) AS cast_val FROM t1;
 double_val	cast_val
 -1e+30	-9223372036854775808
 1e+30	9223372036854775807
+Warnings:
+Warning	1292	Truncated incorrect INTEGER value: '-1e+30'
+Warning	1292	Truncated incorrect INTEGER value: '1e+30'
 DROP TABLE t1;
 select cast('1.2' as decimal(3,2));
 cast('1.2' as decimal(3,2))

sql/field.cc

@@ -4232,6 +4232,7 @@ double Field_double::val_real(void)
 longlong Field_double::val_int(void)
 {
   double j;
+  longlong res;
 #ifdef WORDS_BIGENDIAN
   if (table->s->db_low_byte_first)
   {
@@ -4242,10 +4243,28 @@ longlong Field_double::val_int(void)
     doubleget(j,ptr);
   /* Check whether we fit into longlong range */
   if (j <= (double) LONGLONG_MIN)
-    return (longlong) LONGLONG_MIN;
+  {
+    res= (longlong) LONGLONG_MIN;
+    goto warn;
+  }
   if (j >= (double) (ulonglong) LONGLONG_MAX)
-    return (longlong) LONGLONG_MAX;
+  {
+    res= (longlong) LONGLONG_MAX;
+    goto warn;
+  }
   return (longlong) rint(j);
+
+warn:
+  {
+    char buf[DOUBLE_TO_STRING_CONVERSION_BUFFER_SIZE];
+    String tmp(buf, sizeof(buf), &my_charset_latin1), *str;
+    str= val_str(&tmp, 0);
+    push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
+                        ER_TRUNCATED_WRONG_VALUE,
+                        ER(ER_TRUNCATED_WRONG_VALUE), "INTEGER",
+                        str->c_ptr());
+  }
+  return res;
 }