STRING Join BUG

[fbfans]

'----------------------------------------------------------------------
Scope 'BUG UTF8 And ANSSI TWO MODE
Dim c As String
For n As Integer = 1 To 750000
c = c + WStr("aa") ' c = c + Str("aa") is OK
Next
Print Len(c)
End Scope
'----------------------------------------------------------------------
Scope 'BUG UTF8 Mode
Dim c As String
For n As Integer = 1 To 750000
c = c + "aa" 'c = c + Str("aa") is OK
Next
Print Len(c)
End Scope
'----------------------------------------------------------------------
Scope 'BUG UTF8 and ANSSI TWO Mode
Dim c As String
For n As Integer = 1 To 750000
c = c + "aa"+"bb" 'c=c+ (Str("aa")+Str("bb")) or c &= Str("aa")+Str("bb") IS OK
Next
Print Len(c)
End Scope
'----------------------------------------------------------------------
Scope 'BUG UTF8 and ANSSI TWO Mode
Dim c As String
For n As Integer = 1 To 750000
c = c + Str("aa")+Str("bb") 'c=c+ (Str("aa")+Str("bb")) or c &= Str("aa")+Str("bb") IS OK
Next
Print Len(c)
End Scope

'----------------------------------------------------------------------
Scope
Dim c As String
For n As Integer = 1 To 750000
c = "o" & c
Next
Print Len(c)
End Scope

[fxm]

linked with Memory Leak UTF-8 mode Select Case Case ?

[fbfans]

linked with Memory Leak UTF-8 mode Select Case Case ?

No memory leak occurred, but the program will not return for a long time, like a dead loop program

[fbfans]

Scope
Dim c As String
For n As Integer = 1 To 750000
c = "o" & c
Next
Print Len(c)
End Scope

[SARG]

yes a bit long due to string concatenation in a temporary variable then assignment of this string in c string.
And it seems there is also a memory leak.