UNINIT_VAR() fixes

Restored self-initialization version of UNINIT_VAR() for all gcc versions.
Fixed UNINIT_VAR() usage: it is supposed to be used along with declaration.

Author: svoj

include/my_global.h

@@ -468,7 +468,7 @@ extern "C" int madvise(void *addr, size_t len, int behav);
 /*
    Suppress uninitialized variable warning without generating code.
 */
-#if defined(__GNUC__) && (__GNUC__ < 4 || __GNUC__ == 4 && __GNUC_MINOR__ < 8)
+#if defined(__GNUC__)
 /* GCC specific self-initialization which inhibits the warning. */
 #define UNINIT_VAR(x) x= x
 #elif defined(_lint) || defined(FORCE_INIT_OF_VARS)

sql/item_geofunc.cc

@@ -1152,11 +1152,9 @@ static int setup_relate_func(Geometry *g1, Geometry *g2,
     const char *mask)
 {
   int do_store_shapes=1;
-  uint shape_a, shape_b;
+  uint UNINIT_VAR(shape_a), UNINIT_VAR(shape_b);
   uint n_operands= 0;
   int last_shape_pos;
-  UNINIT_VAR(shape_a);
-  UNINIT_VAR(shape_b);
 
   last_shape_pos= func->get_next_expression_pos();
   if (func->reserve_op_buffer(1))
@@ -2396,12 +2394,10 @@ String *Item_func_pointonsurface::val_str(String *str)
   Geometry *g;
   MBR mbr;
   const char *c_end;
-  double px, py, x0, y0;
+  double UNINIT_VAR(px), UNINIT_VAR(py), x0, y0;
   String *result= 0;
   const Gcalc_scan_iterator::point *pprev= NULL;
   uint32 srid;
-  UNINIT_VAR(px);
-  UNINIT_VAR(py);
 
   null_value= 1;
   if ((args[0]->null_value ||

sql/opt_range.cc

@@ -2933,8 +2933,7 @@ bool calculate_cond_selectivity_for_table(THD *thd, TABLE *table, Item **cond)
         }
         if (i)
         {
-          double selectivity_mult;
-          UNINIT_VAR(selectivity_mult);
+          double UNINIT_VAR(selectivity_mult);
 
           /* 
             There is at least 1-column prefix of columns whose selectivity has

sql/sp_head.cc

@@ -1129,12 +1129,10 @@ sp_head::execute(THD *thd, bool merge_da_on_success)
   const uint status_backup_mask= SERVER_STATUS_CURSOR_EXISTS |
                                  SERVER_STATUS_LAST_ROW_SENT;
   Reprepare_observer *save_reprepare_observer= thd->m_reprepare_observer;
-  Object_creation_ctx *saved_creation_ctx;
+  Object_creation_ctx *UNINIT_VAR(saved_creation_ctx);
   Diagnostics_area *da= thd->get_stmt_da();
   Warning_info sp_wi(da->warning_info_id(), false, true);
 
-  UNINIT_VAR(saved_creation_ctx);
-
   /* this 7*STACK_MIN_SIZE is a complex matter with a long history (see it!) */
   if (check_stack_overrun(thd, 7 * STACK_MIN_SIZE, (uchar*)&old_packet))
     DBUG_RETURN(TRUE);