Fix for handling of unsigned long options on 32-bit platforms that

allowed unintended overflows. (Bug #10351)

mysql-test/r/select_safe.result

@@ -60,9 +60,6 @@ a	b
 3	a
 4	a
 5	a
-SELECT @@MAX_SEEKS_FOR_KEY;
-@@MAX_SEEKS_FOR_KEY
-4294967295
 analyze table t1;
 Table	Op	Msg_type	Msg_text
 test.t1	analyze	status	OK

mysql-test/r/variables.result

@@ -526,14 +526,10 @@ ERROR HY000: Variable 'warning_count' is a read only variable
 set @@global.error_count=1;
 ERROR HY000: Variable 'error_count' is a read only variable
 set @@max_heap_table_size= 4294967296;
-select @@max_heap_table_size;
-@@max_heap_table_size
-4294967296
+select @@max_heap_table_size > 0;
+@@max_heap_table_size > 0
+1
 set global max_heap_table_size= 4294967296;
-select @@max_heap_table_size;
-@@max_heap_table_size
-4294967296
-set @@max_heap_table_size= 4294967296;
-select @@max_heap_table_size;
-@@max_heap_table_size
-4294967296
+select @@global.max_heap_table_size > 0;
+@@global.max_heap_table_size > 0
+1

mysql-test/t/select_safe.test

@@ -56,7 +56,6 @@ SELECT * from t1;
 #
 # Test MAX_SEEKS_FOR_KEY
 #
-SELECT @@MAX_SEEKS_FOR_KEY;
 analyze table t1;
 insert into t1 values (null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a"),(null,"a");
 explain select STRAIGHT_JOIN * from t1,t1 as t2 where t1.b=t2.b;

mysql-test/t/variables.test

@@ -408,11 +408,9 @@ set @@warning_count=1;
 set @@global.error_count=1;
 
 #
-# Bug #10351: Setting max_heap_table_size to 4G fails
+# Bug #10351: Setting ulong variable to > MAX_ULONG fails on 32-bit platform
 #
 set @@max_heap_table_size= 4294967296;
-select @@max_heap_table_size;
+select @@max_heap_table_size > 0;
 set global max_heap_table_size= 4294967296;
-select @@max_heap_table_size;
-set @@max_heap_table_size= 4294967296;
-select @@max_heap_table_size;
+select @@global.max_heap_table_size > 0;

sql/mysqld.cc

@@ -5371,7 +5371,7 @@ The minimum value for this variable is 4096.",
     "Limit assumed max number of seeks when looking up rows based on a key",
     (gptr*) &global_system_variables.max_seeks_for_key,
     (gptr*) &max_system_variables.max_seeks_for_key, 0, GET_ULONG,
-    REQUIRED_ARG, UINT_MAX32, 1, UINT_MAX32, 0, 1, 0 },
+    REQUIRED_ARG, ~0L, 1, ~0L, 0, 1, 0 },
   {"max_sort_length", OPT_MAX_SORT_LENGTH,
    "The number of bytes to use when sorting BLOB or TEXT values (only the first max_sort_length bytes of each value are used; the rest are ignored).",
    (gptr*) &global_system_variables.max_sort_length,

sql/set_var.cc

@@ -1422,6 +1422,12 @@ bool sys_var_thd_ulong::update(THD *thd, set_var *var)
 {
   ulonglong tmp= var->save_result.ulonglong_value;
 
+#if SIZEOF_LONG != SIZEOF_LONGLONG
+  /* Avoid overflow on 32-bit platforms. */
+  if (tmp > ULONG_MAX)
+    tmp= ULONG_MAX;
+#endif
+
   /* Don't use bigger value than given with --maximum-variable-name=.. */
   if ((ulong) tmp > max_system_variables.*offset)
     tmp= max_system_variables.*offset;