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.

client/mysql.cc:
  Meaningless pointer dereferences.
client/mysql_upgrade.c:
  Check whether reading from the file succeeded.
extra/comp_err.c:
  Unused.
extra/yassl/src/yassl_imp.cpp:
  Skip instead of reading data that is discarded.
include/my_pthread.h:
  Variable is only used in debug builds.
include/mysys_err.h:
  Add new error messages.
mysys/errors.c:
  Add new error message for permission related functions.
mysys/mf_iocache.c:
  Variable is only checked under THREAD.
mysys/my_copy.c:
  Raise a error if chmod or chown fails.
mysys/my_redel.c:
  Raise a error if chmod or chown fails.
regex/engine.c:
  Use a equivalent variable for the assert.
server-tools/instance-manager/instance_options.cc:
  Unused.
sql/field.cc:
  Unused.
sql/item.cc:
  Unused.
sql/log.cc:
  Do not ignore the return value of freopen: only set buffer if
  reopening succeeds.
  
  Adjust doxygen comment to the right function.
  
  Pass message lenght to log function.
sql/mysqld.cc:
  Do not ignore the return value of freopen: only set buffer if
  reopening succeeds.
sql/partition_info.cc:
  Unused.
sql/slave.cc:
  No need to set pointer to the address of '\0'.
sql/spatial.cc:
  Unused. Left for historical purposes.
sql/sql_acl.cc:
  Unused.
sql/sql_base.cc:
  Pointers are always set to the same variables.
sql/sql_parse.cc:
  End statement if reading fails.
  
  Store the buffer after it has actually been updated.
sql/sql_repl.cc:
  No need to set pointer to the address of '\0'.
sql/sql_show.cc:
  Put variable under the same ifdef block.
sql/udf_example.c:
  Set null pointer flag appropriately.
storage/csv/ha_tina.cc:
  Meaningless dereferences.
storage/example/ha_example.cc:
  Return the error since it's available.
storage/myisam/mi_locking.c:
  Remove unused and dead code.

1 files changed, 6 insertions, 7 deletions

diff --git a/sql/sql_load.cc b/sql/sql_load.cc
index ee7481234a4..a4cf46b35e8 100644
--- a/sql/sql_load.cc
+++ b/sql/sql_load.cc
@@ -128,6 +128,7 @@ int mysql_load(THD *thd,sql_exchange *ex,TABLE_LIST *table_list,
   bool is_fifo=0;
 #ifndef EMBEDDED_LIBRARY
   LOAD_FILE_INFO lf_info;
+  THD::killed_state killed_status;
 #endif
   char *db = table_list->db;			// This is never null
   /*
@@ -138,7 +139,6 @@ int mysql_load(THD *thd,sql_exchange *ex,TABLE_LIST *table_list,
   char *tdb= thd->db ? thd->db : db;		// Result is never null
   ulong skip_lines= ex->skip_lines;
   bool transactional_table;
-  THD::killed_state killed_status= THD::NOT_KILLED;
   DBUG_ENTER("mysql_load");
 
 #ifdef EMBEDDED_LIBRARY
@@ -455,7 +455,11 @@ int mysql_load(THD *thd,sql_exchange *ex,TABLE_LIST *table_list,
                     error=1;
                     thd->killed= THD::KILL_QUERY;
                   };);
-  killed_status= (error == 0)? THD::NOT_KILLED : thd->killed;
+
+#ifndef EMBEDDED_LIBRARY
+  killed_status= (error == 0) ? THD::NOT_KILLED : thd->killed;
+#endif
+
   /*
     We must invalidate the table in query cache before binlog writing and
     ha_autocommit_...
@@ -708,12 +712,9 @@ read_fixed_length(THD *thd, COPY_INFO &info, TABLE_LIST *table_list,
   List_iterator_fast<Item> it(fields_vars);
   Item_field *sql_field;
   TABLE *table= table_list->table;
-  ulonglong id;
   bool err;
   DBUG_ENTER("read_fixed_length");
 
-  id= 0;
- 
   while (!read_info.read_fixed_length())
   {
     if (thd->killed)
@@ -839,12 +840,10 @@ read_sep_field(THD *thd, COPY_INFO &info, TABLE_LIST *table_list,
   Item *item;
   TABLE *table= table_list->table;
   uint enclosed_length;
-  ulonglong id;
   bool err;
   DBUG_ENTER("read_sep_field");
 
   enclosed_length=enclosed.length();
-  id= 0;
 
   for (;;it.rewind())
   {