diff --git a/mysql-test/r/func_misc.result b/mysql-test/r/func_misc.result
index 39bf1470afe..946a07d0eb2 100644
--- a/mysql-test/r/func_misc.result
+++ b/mysql-test/r/func_misc.result
@@ -190,6 +190,12 @@ ERROR 21000: Operand should contain 1 column(s)
 drop table table_26093;
 drop function func_26093_a;
 drop function func_26093_b;
+create table t1 (a int not null);
+insert into t1 values (-1), (-2);
+select min(a) from t1 group by inet_ntoa(a);
+min(a)
+-2
+drop table t1;
 End of 5.0 tests
 select connection_id() > 0;
 connection_id() > 0
diff --git a/mysql-test/r/insert.result b/mysql-test/r/insert.result
index 8dbba4d454a..a884b51eada 100644
--- a/mysql-test/r/insert.result
+++ b/mysql-test/r/insert.result
@@ -499,4 +499,18 @@ i
 2
 2
 DROP TABLE t1, t2;
+CREATE TABLE t1 (c1 INT NOT NULL);
+INSERT INTO t1 VALUES(4188.32999999999992724042385816574096679687500),
+('4188.32999999999992724042385816574096679687500'), (4188);
+SELECT * FROM t1;
+c1
+4188
+4188
+4188
+CREATE TABLE t2 (c1 BIGINT);
+INSERT INTO t2 VALUES('15449237462.0000000000');
+SELECT * FROM t2;
+c1
+15449237462
+DROP TABLE t1, t2;
 End of 5.0 tests.
diff --git a/mysql-test/r/log_state.result b/mysql-test/r/log_state.result
index 3a3ef584ce3..407d93cf321 100644
--- a/mysql-test/r/log_state.result
+++ b/mysql-test/r/log_state.result
@@ -175,3 +175,16 @@ SET GLOBAL slow_query_log = ON;
 SET GLOBAL READ_ONLY = OFF;
 SET GLOBAL general_log = @old_general_log_state;
 SET GLOBAL slow_query_log = @old_slow_log_state;
+set @old_general_log_file= @@global.general_log_file;
+set @old_slow_query_log_file= @@global.slow_query_log_file;
+set global general_log_file= concat('/not exiting path/log.maste', 'r');
+ERROR 42000: Variable 'general_log_file' can't be set to the value of '/not exiting path/log.master'
+set global general_log_file= NULL;
+ERROR 42000: Variable 'general_log_file' can't be set to the value of 'NULL'
+set global slow_query_log_file= concat('/not exiting path/log.maste', 'r');
+ERROR 42000: Variable 'slow_query_log_file' can't be set to the value of '/not exiting path/log.master'
+set global slow_query_log_file= NULL;
+ERROR 42000: Variable 'slow_query_log_file' can't be set to the value of 'NULL'
+set global general_log_file= @old_general_log_file;
+set global slow_query_log_file= @old_slow_query_log_file;
+End of 5.1 tests
diff --git a/mysql-test/r/status.result b/mysql-test/r/status.result
index db75044ee5d..c95b09597fc 100644
--- a/mysql-test/r/status.result
+++ b/mysql-test/r/status.result
@@ -8,6 +8,8 @@ VARIABLE_NAME	VARIABLE_VALUE
 TABLE_LOCKS_IMMEDIATE	2
 TABLE_LOCKS_WAITED	0
 SET SQL_LOG_BIN=0;
+set @old_general_log = @@global.general_log;
+set global general_log = 'OFF';
 drop table if exists t1;
 create table t1(n int) engine=myisam;
 insert into t1 values(1);
@@ -20,6 +22,7 @@ show status like 'Table_locks_waited';
 Variable_name	Value
 Table_locks_waited	1
 drop table t1;
+set global general_log = @old_general_log;
 select 1;
 1
 1
diff --git a/mysql-test/t/func_misc.test b/mysql-test/t/func_misc.test
index 01eff55d1f6..db4df9ef244 100644
--- a/mysql-test/t/func_misc.test
+++ b/mysql-test/t/func_misc.test
@@ -198,6 +198,14 @@ drop table table_26093;
 drop function func_26093_a;
 drop function func_26093_b;
 
+#
+# Bug #31349: ERROR 1062 (23000): Duplicate entry '' for key 'group_key'
+#
+create table t1 (a int not null);
+insert into t1 values (-1), (-2);
+select min(a) from t1 group by inet_ntoa(a);
+drop table t1;
+
 --echo End of 5.0 tests
 
 #
diff --git a/mysql-test/t/insert.test b/mysql-test/t/insert.test
index 3d32da9c3b7..59da875bb24 100644
--- a/mysql-test/t/insert.test
+++ b/mysql-test/t/insert.test
@@ -387,5 +387,20 @@ SELECT * FROM t2;
 
 DROP TABLE t1, t2;
 
+#
+# Bug #30453: String not cast to int correctly
+#
+
+CREATE TABLE t1 (c1 INT NOT NULL);
+INSERT INTO t1 VALUES(4188.32999999999992724042385816574096679687500),
+('4188.32999999999992724042385816574096679687500'), (4188);
+SELECT * FROM t1;
+
+CREATE TABLE t2 (c1 BIGINT);
+INSERT INTO t2 VALUES('15449237462.0000000000');
+SELECT * FROM t2;
+
+DROP TABLE t1, t2;
+
 --echo End of 5.0 tests.
 
diff --git a/mysql-test/t/log_state.test b/mysql-test/t/log_state.test
index c67da261ef1..ec3644cbff1 100644
--- a/mysql-test/t/log_state.test
+++ b/mysql-test/t/log_state.test
@@ -189,3 +189,23 @@ disconnect con1;
 # Remove the log files that was created in the "default location"
 # i.e var/run
 --remove_file $MYSQLTEST_VARDIR/run/master.log
+
+#
+# Bug #31604: server crash when setting slow_query_log_file/general_log_file
+#
+set @old_general_log_file= @@global.general_log_file;
+set @old_slow_query_log_file= @@global.slow_query_log_file;
+
+--error 1231
+set global general_log_file= concat('/not exiting path/log.maste', 'r');
+--error 1231
+set global general_log_file= NULL;
+--error 1231
+set global slow_query_log_file= concat('/not exiting path/log.maste', 'r');
+--error 1231
+set global slow_query_log_file= NULL;
+
+set global general_log_file= @old_general_log_file;
+set global slow_query_log_file= @old_slow_query_log_file;
+
+--echo End of 5.1 tests
diff --git a/mysql-test/t/status.test b/mysql-test/t/status.test
index 1cd5aa1726a..6a11791924a 100644
--- a/mysql-test/t/status.test
+++ b/mysql-test/t/status.test
@@ -21,6 +21,8 @@ select * from information_schema.session_status where variable_name like 'Table_
 connection con1;
 # ++Immediate = 3
 SET SQL_LOG_BIN=0;
+set @old_general_log = @@global.general_log;                                      
+set global general_log = 'OFF';
 --disable_warnings
 # ++Immediate = 4
 drop table if exists t1;
@@ -60,6 +62,7 @@ reap;
 # ++Immediate = 16 + $wait_condition_reps
 show status like 'Table_locks_waited';
 drop table t1;
+set global general_log = @old_general_log;
 
 disconnect con2;
 disconnect con1;
diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h
index 155f8457156..2322f0aacc2 100644
--- a/sql/item_strfunc.h
+++ b/sql/item_strfunc.h
@@ -657,7 +657,12 @@ public:
     }
   String* val_str(String* str);
   const char *func_name() const { return "inet_ntoa"; }
-  void fix_length_and_dec() { decimals = 0; max_length=3*8+7; }
+  void fix_length_and_dec() 
+  { 
+    decimals= 0; 
+    max_length= 3 * 8 + 7; 
+    maybe_null= 1;
+  }
 };
 
 class Item_func_quote :public Item_str_func
diff --git a/sql/set_var.cc b/sql/set_var.cc
index 9a6ad9ce662..b6b102aa4d0 100644
--- a/sql/set_var.cc
+++ b/sql/set_var.cc
@@ -2102,18 +2102,24 @@ void sys_var_log_state::set_default(THD *thd, enum_var_type type)
 
 static int  sys_check_log_path(THD *thd,  set_var *var)
 {
-  char path[FN_REFLEN];
+  char path[FN_REFLEN], buff[FN_REFLEN];
   MY_STAT f_stat;
-  const char *var_path= var->value->str_value.ptr();
+  String str(buff, sizeof(buff), system_charset_info), *res;
+  const char *log_file_str;
+      
+  if (!(res= var->value->val_str(&str)))
+    goto err;
+
+  log_file_str= res->c_ptr();
   bzero(&f_stat, sizeof(MY_STAT));
 
-  (void) unpack_filename(path, var_path);
+  (void) unpack_filename(path, log_file_str);
   if (my_stat(path, &f_stat, MYF(0)))
   {
     /* Check if argument is a file and we have 'write' permission */
     if (!MY_S_ISREG(f_stat.st_mode) ||
         !(f_stat.st_mode & MY_S_IWRITE))
-      return -1;
+      goto err;
   }
   else
   {
@@ -2122,11 +2128,16 @@ static int  sys_check_log_path(THD *thd,  set_var *var)
       Check if directory exists and 
       we have permission to create file & write to file
     */
-    (void) dirname_part(path, var_path, &path_length);
+    (void) dirname_part(path, log_file_str, &path_length);
     if (my_access(path, (F_OK|W_OK)))
-      return -1;
+      goto err;
   }
   return 0;
+
+err:
+  my_error(ER_WRONG_VALUE_FOR_VAR, MYF(0), var->var->name, 
+           res ? log_file_str : "NULL");
+  return 1;
 }
 
 
diff --git a/strings/ctype-simple.c b/strings/ctype-simple.c
index 6b71f29f0d2..b5e5e2184ba 100644
--- a/strings/ctype-simple.c
+++ b/strings/ctype-simple.c
@@ -1561,14 +1561,18 @@ my_strntoull10rnd_8bit(CHARSET_INFO *cs __attribute__((unused)),
       }
       else
         addon= (*str >= '5');
-      for ( ; str < end && (ch= (uchar) (*str - '0')) < 10; str++)
+      if (!dot)
       {
-        if (!dot)
-          shift++;
+        for ( ; str < end && (ch= (uchar) (*str - '0')) < 10; shift++, str++);
+        if (str < end && *str == '.')
+        {
+          str++;
+          for ( ; str < end && (ch= (uchar) (*str - '0')) < 10; str++);
+        }
       }
-      if (str < end && *str == '.' && !dot)
+      else
       {
-        str++;
+        shift= dot - str;
         for ( ; str < end && (ch= (uchar) (*str - '0')) < 10; str++);
       }
       goto exp;