Fix some __attribute__((nonnull)) misuse

This fixes warnings that were emitted when running InnoDB test
suites on a debug server that was compiled with GCC 7.1.0 using
the flags -O3 -fsanitize=undefined.

thd_requested_durability(): XtraDB can call this with trx->mysql_thd=NULL.
Remove the function in InnoDB, because it is not used there.

calc_row_difference(): Do not call memcmp(o_ptr, NULL, 0).

innobase_index_name_is_reserved(): This can be called with
key_info=NULL, num_of_keys=0.

innobase_dropping_foreign(), innobase_check_foreigns_low(),
innobase_check_foreigns(): This can be called with
drop_fk=NULL, n_drop_fk=0.

rec_convert_dtuple_to_rec_comp(): Do not invoke memcpy(end, NULL, 0).

storage/innobase/handler/ha_innodb.cc

@@ -1321,19 +1321,6 @@ thd_is_replication_slave_thread(
 	return((ibool) thd_slave_thread(thd));
 }
 
-/******************************************************************//**
-Gets information on the durability property requested by thread.
-Used when writing either a prepare or commit record to the log
-buffer. @return the durability property. */
-UNIV_INTERN
-enum durability_properties
-thd_requested_durability(
-/*=====================*/
-	const THD* thd)	/*!< in: thread handle */
-{
-	return(thd_get_durability_property(thd));
-}
-
 /******************************************************************//**
 Returns true if transaction should be flagged as read-only.
 @return	true if the thd is marked as read-only */
@@ -7519,8 +7506,8 @@ calc_row_difference(
 			}
 		}
 
-		if (o_len != n_len || (o_len != UNIV_SQL_NULL &&
-					0 != memcmp(o_ptr, n_ptr, o_len))) {
+		if (o_len != n_len || (o_len != 0 && o_len != UNIV_SQL_NULL
+				       && 0 != memcmp(o_ptr, n_ptr, o_len))) {
 			/* The field has changed */
 
 			ufield = uvect->fields + n_changed;

storage/innobase/handler/ha_innodb.h

 /*****************************************************************************
 
 Copyright (c) 2000, 2016, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2013, 2016, MariaDB Corporation.
+Copyright (c) 2013, 2017, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -476,7 +476,7 @@ innobase_index_name_is_reserved(
 	const KEY*	key_info,	/*!< in: Indexes to be created */
 	ulint		num_of_keys)	/*!< in: Number of indexes to
 					be created. */
-	MY_ATTRIBUTE((nonnull, warn_unused_result));
+	MY_ATTRIBUTE((nonnull(1), warn_unused_result));
 
 /*****************************************************************//**
 Determines InnoDB table flags.

storage/innobase/handler/handler0alter.cc

 /*****************************************************************************
 
 Copyright (c) 2005, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2017, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -2277,10 +2278,10 @@ online_retry_drop_indexes_with_trx(
 @param drop_fk		constraints being dropped
 @param n_drop_fk	number of constraints that are being dropped
 @return whether the constraint is being dropped */
-inline MY_ATTRIBUTE((pure, nonnull, warn_unused_result))
+MY_ATTRIBUTE((pure, nonnull(1), warn_unused_result))
+inline
 bool
 innobase_dropping_foreign(
-/*======================*/
 	const dict_foreign_t*	foreign,
 	dict_foreign_t**	drop_fk,
 	ulint			n_drop_fk)
@@ -2304,10 +2305,10 @@ column that is being dropped or modified to NOT NULL.
 @retval true		Not allowed (will call my_error())
 @retval false		Allowed
 */
-static MY_ATTRIBUTE((pure, nonnull, warn_unused_result))
+MY_ATTRIBUTE((pure, nonnull(1,4), warn_unused_result))
+static
 bool
 innobase_check_foreigns_low(
-/*========================*/
 	const dict_table_t*	user_table,
 	dict_foreign_t**	drop_fk,
 	ulint			n_drop_fk,
@@ -2404,10 +2405,10 @@ column that is being dropped or modified to NOT NULL.
 @retval true		Not allowed (will call my_error())
 @retval false		Allowed
 */
-static MY_ATTRIBUTE((pure, nonnull, warn_unused_result))
+MY_ATTRIBUTE((pure, nonnull(1,2,3,4), warn_unused_result))
+static
 bool
 innobase_check_foreigns(
-/*====================*/
 	Alter_inplace_info*	ha_alter_info,
 	const TABLE*		altered_table,
 	const TABLE*		old_table,

storage/innobase/include/ha_prototypes.h

@@ -126,18 +126,6 @@ thd_is_replication_slave_thread(
 /*============================*/
 	THD*	thd);	/*!< in: thread handle */
 
-/******************************************************************//**
-Gets information on the durability property requested by thread.
-Used when writing either a prepare or commit record to the log
-buffer.
-@return the durability property. */
-UNIV_INTERN
-enum durability_properties
-thd_requested_durability(
-/*=====================*/
-	const THD* thd)	/*!< in: thread handle */
-	MY_ATTRIBUTE((nonnull, warn_unused_result));
-
 /******************************************************************//**
 Returns true if the transaction this thread is processing has edited
 non-transactional tables. Used by the deadlock detector when deciding

storage/innobase/rem/rem0rec.cc

@@ -1285,9 +1285,11 @@ rec_convert_dtuple_to_rec_comp(
 			}
 		}
 
+		if (len) {
 			memcpy(end, dfield_get_data(field), len);
 			end += len;
 		}
+	}
 }
 
 /*********************************************************//**

storage/xtradb/handler/ha_innodb.cc

@@ -8202,8 +8202,8 @@ calc_row_difference(
 			}
 		}
 
-		if (o_len != n_len || (o_len != UNIV_SQL_NULL &&
-					0 != memcmp(o_ptr, n_ptr, o_len))) {
+		if (o_len != n_len || (o_len != 0 && o_len != UNIV_SQL_NULL
+				       && 0 != memcmp(o_ptr, n_ptr, o_len))) {
 			/* The field has changed */
 
 			ufield = uvect->fields + n_changed;

storage/xtradb/handler/ha_innodb.h

@@ -484,7 +484,7 @@ innobase_index_name_is_reserved(
 	const KEY*	key_info,	/*!< in: Indexes to be created */
 	ulint		num_of_keys)	/*!< in: Number of indexes to
 					be created. */
-	MY_ATTRIBUTE((nonnull, warn_unused_result));
+	MY_ATTRIBUTE((nonnull(1), warn_unused_result));
 
 /*****************************************************************//**
 Determines InnoDB table flags.

storage/xtradb/handler/handler0alter.cc

@@ -2278,10 +2278,10 @@ online_retry_drop_indexes_with_trx(
 @param drop_fk		constraints being dropped
 @param n_drop_fk	number of constraints that are being dropped
 @return whether the constraint is being dropped */
-inline MY_ATTRIBUTE((pure, nonnull, warn_unused_result))
+MY_ATTRIBUTE((pure, nonnull(1), warn_unused_result))
+inline
 bool
 innobase_dropping_foreign(
-/*======================*/
 	const dict_foreign_t*	foreign,
 	dict_foreign_t**	drop_fk,
 	ulint			n_drop_fk)
@@ -2305,10 +2305,10 @@ column that is being dropped or modified to NOT NULL.
 @retval true		Not allowed (will call my_error())
 @retval false		Allowed
 */
-static MY_ATTRIBUTE((pure, nonnull, warn_unused_result))
+MY_ATTRIBUTE((pure, nonnull(1,4), warn_unused_result))
+static
 bool
 innobase_check_foreigns_low(
-/*========================*/
 	const dict_table_t*	user_table,
 	dict_foreign_t**	drop_fk,
 	ulint			n_drop_fk,
@@ -2405,10 +2405,10 @@ column that is being dropped or modified to NOT NULL.
 @retval true		Not allowed (will call my_error())
 @retval false		Allowed
 */
-static MY_ATTRIBUTE((pure, nonnull, warn_unused_result))
+MY_ATTRIBUTE((pure, nonnull(1,2,3,4), warn_unused_result))
+static
 bool
 innobase_check_foreigns(
-/*====================*/
 	Alter_inplace_info*	ha_alter_info,
 	const TABLE*		altered_table,
 	const TABLE*		old_table,

storage/xtradb/include/ha_prototypes.h

 /*****************************************************************************
 
 Copyright (c) 2006, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2017, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -143,7 +144,7 @@ enum durability_properties
 thd_requested_durability(
 /*=====================*/
 	const THD* thd)	/*!< in: thread handle */
-	MY_ATTRIBUTE((nonnull, warn_unused_result));
+	MY_ATTRIBUTE((warn_unused_result));
 
 /******************************************************************//**
 Returns true if the transaction this thread is processing has edited

storage/xtradb/rem/rem0rec.cc

@@ -1290,9 +1290,11 @@ rec_convert_dtuple_to_rec_comp(
 			}
 		}
 
+		if (len) {
 			memcpy(end, dfield_get_data(field), len);
 			end += len;
 		}
+	}
 }
 
 /*********************************************************//**