Bug#45168: assertion with convert() and empty set value

      
The assertion in String::copy was added in order to avoid
valgrind errors when the destination was the same as the source.
Eased restriction to allow for the case when str == NULL.

1 files changed, 12 insertions, 3 deletions

diff --git a/sql/sql_string.cc b/sql/sql_string.cc
index 61731f3b984..7759985ba85 100644
--- a/sql/sql_string.cc
+++ b/sql/sql_string.cc
@@ -322,14 +322,23 @@ bool String::set_or_copy_aligned(const char *str,uint32 arg_length,
   return copy_aligned(str, arg_length, offset, cs);
 }
 
-	/* Copy with charset conversion */
+
+/**
+   Copies the character data into this String, with optional character set
+   conversion.
+
+   @return
+   FALSE ok
+   TRUE  Could not allocate result buffer
+
+*/
 
 bool String::copy(const char *str, uint32 arg_length,
 		  CHARSET_INFO *from_cs, CHARSET_INFO *to_cs, uint *errors)
 {
   uint32 offset;
-  
-  DBUG_ASSERT(str != Ptr);
+
+  DBUG_ASSERT(!str || str != Ptr);
   
   if (!needs_conversion(arg_length, from_cs, to_cs, &offset))
   {