Bug#45288: pb2 returns a lot of compilation warnings on linux

Fix warnings flagged by the new warning option -Wunused-but-set-variable
that was added to GCC 4.6 and that is enabled by -Wunused and -Wall. The
option causes a warning whenever a local variable is assigned to but is
later unused. It also warns about meaningless pointer dereferences.

5 files changed, 6 insertions, 30 deletions

diff --git a/storage/csv/ha_tina.cc b/storage/csv/ha_tina.cc
index e3bc7f55dd2..5a3399b2401 100644
--- a/storage/csv/ha_tina.cc
+++ b/storage/csv/ha_tina.cc
@@ -468,7 +468,7 @@ int ha_tina::encode_quote(uchar *buf)
     const char *ptr;
     const char *end_ptr;
     const bool was_null= (*field)->is_null();
-    
+
     /*
       assistance for backwards compatibility in production builds.
       note: this will not work for ENUM columns.
@@ -480,7 +480,7 @@ int ha_tina::encode_quote(uchar *buf)
     }
 
     (*field)->val_str(&attribute,&attribute);
-    
+
     if (was_null)
       (*field)->set_null();
 
@@ -491,34 +491,30 @@ int ha_tina::encode_quote(uchar *buf)
 
       buffer.append('"');
 
-      while (ptr < end_ptr) 
+      for (; ptr < end_ptr; ptr++)
       {
         if (*ptr == '"')
         {
           buffer.append('\\');
           buffer.append('"');
-          *ptr++;
         }
         else if (*ptr == '\r')
         {
           buffer.append('\\');
           buffer.append('r');
-          *ptr++;
         }
         else if (*ptr == '\\')
         {
           buffer.append('\\');
           buffer.append('\\');
-          *ptr++;
         }
         else if (*ptr == '\n')
         {
           buffer.append('\\');
           buffer.append('n');
-          *ptr++;
         }
         else
-          buffer.append(*ptr++);
+          buffer.append(*ptr);
       }
       buffer.append('"');
     }
diff --git a/storage/example/ha_example.cc b/storage/example/ha_example.cc
index 604722c3c8c..2a4fe538c85 100644
--- a/storage/example/ha_example.cc
+++ b/storage/example/ha_example.cc
@@ -153,7 +153,7 @@ static int example_done_func(void *p)
   hash_free(&example_open_tables);
   pthread_mutex_destroy(&example_mutex);
 
-  DBUG_RETURN(0);
+  DBUG_RETURN(error);
 }
 
 
diff --git a/storage/myisam/mi_locking.c b/storage/myisam/mi_locking.c
index 342efff4842..589b9cf89b7 100644
--- a/storage/myisam/mi_locking.c
+++ b/storage/myisam/mi_locking.c
@@ -29,7 +29,6 @@ int mi_lock_database(MI_INFO *info, int lock_type)
   int error;
   uint count;
   MYISAM_SHARE *share=info->s;
-  uint flag;
   DBUG_ENTER("mi_lock_database");
   DBUG_PRINT("enter",("lock_type: %d  old lock %d  r_locks: %u  w_locks: %u "
                       "global_changed:  %d  open_count: %u  name: '%s'",
@@ -48,7 +47,7 @@ int mi_lock_database(MI_INFO *info, int lock_type)
     DBUG_RETURN(0);
   }
 
-  flag=error=0;
+  error= 0;
   pthread_mutex_lock(&share->intern_lock);
   if (share->kfile >= 0)		/* May only be false on windows */
   {
@@ -120,14 +119,12 @@ int mi_lock_database(MI_INFO *info, int lock_type)
 	{
 	  if (share->r_locks)
 	  {					/* Only read locks left */
-	    flag=1;
 	    if (my_lock(share->kfile,F_RDLCK,0L,F_TO_EOF,
 			MYF(MY_WME | MY_SEEK_NOT_DONE)) && !error)
 	      error=my_errno;
 	  }
 	  else if (!share->w_locks)
 	  {					/* No more locks */
-	    flag=1;
 	    if (my_lock(share->kfile,F_UNLCK,0L,F_TO_EOF,
 			MYF(MY_WME | MY_SEEK_NOT_DONE)) && !error)
 	      error=my_errno;
@@ -148,7 +145,6 @@ int mi_lock_database(MI_INFO *info, int lock_type)
         */
 	if (share->w_locks == 1)
 	{
-	  flag=1;
           if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,
 		      MYF(MY_SEEK_NOT_DONE)))
 	  {
@@ -163,7 +159,6 @@ int mi_lock_database(MI_INFO *info, int lock_type)
       }
       if (!share->r_locks && !share->w_locks)
       {
-	flag=1;
 	if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,
 		    info->lock_wait | MY_SEEK_NOT_DONE))
 	{
@@ -188,7 +183,6 @@ int mi_lock_database(MI_INFO *info, int lock_type)
       {						/* Change READONLY to RW */
 	if (share->r_locks == 1)
 	{
-	  flag=1;
 	  if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,
 		      MYF(info->lock_wait | MY_SEEK_NOT_DONE)))
 	  {
@@ -205,7 +199,6 @@ int mi_lock_database(MI_INFO *info, int lock_type)
       {
 	if (!share->w_locks)
 	{
-	  flag=1;
 	  if (my_lock(share->kfile,lock_type,0L,F_TO_EOF,
 		      info->lock_wait | MY_SEEK_NOT_DONE))
 	  {
@@ -252,11 +245,6 @@ int mi_lock_database(MI_INFO *info, int lock_type)
   }
 #endif
   pthread_mutex_unlock(&share->intern_lock);
-#if defined(FULL_LOG) || defined(_lint)
-  lock_type|=(int) (flag << 8);		/* Set bit to set if real lock */
-  myisam_log_command(MI_LOG_LOCK,info,(uchar*) &lock_type,sizeof(lock_type),
-		     error);
-#endif
   DBUG_RETURN(error);
 } /* mi_lock_database */
 
diff --git a/storage/myisam/rt_split.c b/storage/myisam/rt_split.c
index 88cf643faf9..03d22de68fa 100644
--- a/storage/myisam/rt_split.c
+++ b/storage/myisam/rt_split.c
@@ -255,7 +255,6 @@ int rtree_split_page(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *page, uchar *key,
   SplitStruct *stop;
   double *coord_buf;
   double *next_coord;
-  double *old_coord;
   int n_dim;
   uchar *source_cur, *cur1, *cur2;
   uchar *new_page= info->buff;
@@ -293,8 +292,6 @@ int rtree_split_page(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *page, uchar *key,
   rtree_d_mbr(keyinfo->seg, key, key_length, cur->coords);
   cur->key = key;
 
-  old_coord = next_coord;
-
   if (split_rtree_node(task, max_keys + 1,
        mi_getint(page) + full_length + 2, full_length, 
        rt_PAGE_MIN_SIZE(keyinfo->block_length),
diff --git a/storage/myisammrg/myrg_open.c b/storage/myisammrg/myrg_open.c
index 5fcbe0c3297..18f8aa8d2c0 100644
--- a/storage/myisammrg/myrg_open.c
+++ b/storage/myisammrg/myrg_open.c
@@ -227,9 +227,7 @@ MYRG_INFO *myrg_parent_open(const char *parent_name,
   int       save_errno;
   int       insert_method;
   uint      length;
-  uint      dir_length;
   uint      child_count;
-  size_t    name_buff_length;
   File      fd;
   IO_CACHE  file_cache;
   char      parent_name_buff[FN_REFLEN * 2];
@@ -299,7 +297,6 @@ MYRG_INFO *myrg_parent_open(const char *parent_name,
   }
 
   /* Call callback for each child. */
-  dir_length= dirname_part(parent_name_buff, parent_name, &name_buff_length);
   my_b_seek(&file_cache, 0);
   while ((length= my_b_gets(&file_cache, child_name_buff, FN_REFLEN - 1)))
   {
@@ -379,7 +376,6 @@ int myrg_attach_children(MYRG_INFO *m_info, int handle_locking,
 {
   ulonglong  file_offset;
   MI_INFO    *myisam;
-  int        rc;
   int        errpos;
   int        save_errno;
   uint       idx;
@@ -398,7 +394,6 @@ int myrg_attach_children(MYRG_INFO *m_info, int handle_locking,
     here and in ha_myisammrg::store_lock() forces consistent data.
   */
   pthread_mutex_lock(&m_info->mutex);
-  rc= 1;
   errpos= 0;
   file_offset= 0;
   min_keys= 0;