Fix bug# 54901 assert during recovery when binlog enabled.

Remove the pure attribute from a function. The function doesn't qualify as
a pure function because it has a side-effect (modifies its parameter). Add
a clarifying comment to another function's declaration.

storage/innobase/include/buf0buf.h

@@ -869,7 +869,8 @@ buf_page_set_accessed(
 	__attribute__((nonnull));
 /*********************************************************************//**
 Gets the buf_block_t handle of a buffered file block if an uncompressed
-page frame exists, or NULL.
+page frame exists, or NULL. Note: even though bpage is not declared a
+const we don't update its value. It is safe to make this pure.
 @return	control block, or NULL */
 UNIV_INLINE
 buf_block_t*

storage/innobase/include/mach0data.h

@@ -289,8 +289,7 @@ mach_ull_parse_compressed(
 /*======================*/
 	byte*		ptr,	/*!< in: pointer to buffer from where to read */
 	byte*		end_ptr,/*!< in: pointer to end of the buffer */
-	ib_uint64_t*	val)	/*!< out: read value */
-	__attribute__((nonnull, pure));
+	ib_uint64_t*	val);	/*!< out: read value */
 #ifndef UNIV_HOTBACKUP
 /*********************************************************//**
 Reads a double. It is stored in a little-endian format.