fbc: typeini - allow implicit up-casting for NEW()

- revert behaviour where NEW() disallowed up-casting
- allow up-casting for NEW() initializers
- for example, this is now - allowed again:

    type parent
        i as integer
    end type
    type child extends parent
        j as integer
    end type

    dim c as child

    '' implicit up-cast of c to parent
    dim p as parent ptr = new parent( c )

src/compiler/parser-decl-symb-init.bas

@@ -633,6 +633,7 @@ function cInitializer _
 	'' [x] top level -> allow up-casting
 	'' [x] nested UDT initialization -> do not allow up-casting
 	'' [ ] array element initialization -> allow up-casting
+	'' [x] NEW() -> allow up-casting
 
 	'' No override in options?
 	if( (options and FB_INIOPT_NOUPCAST) = 0 ) then
@@ -641,8 +642,10 @@ function cInitializer _
 		if( ctx.last_ctx = NULL ) then
 			ctx.options and= not FB_INIOPT_NOUPCAST
 
-		'' anything else, assume no upcasting
-		else
+		'' up-casting not explicitly enabled?
+		elseif( (options and FB_INIOPT_UPCAST) = 0 ) then
+
+			'' then anything else, assume no up-casting
 			ctx.options or= FB_INIOPT_NOUPCAST
 
 		end if

src/compiler/parser-quirk-mem.bas

@@ -190,7 +190,7 @@ function cOperatorNew( ) as ASTNODE ptr
 					lexSkipToken( )
 				end if
 			else
-				initexpr = cInitializer( tmp, FB_INIOPT_ISINI or FB_INIOPT_NOUPCAST, dtype, subtype )
+				initexpr = cInitializer( tmp, FB_INIOPT_ISINI or FB_INIOPT_UPCAST, dtype, subtype )
 				if( initexpr = NULL ) then
 					errReport( FB_ERRMSG_EXPECTEDEXPRESSION )
 				end if

src/compiler/parser.bi

@@ -227,6 +227,7 @@ enum FB_INIOPT
 	FB_INIOPT_ISINI             = &h00000001  '' initializer (not an expression)
 	FB_INIOPT_ISOBJ             = &h00000002  '' object with constructor
 	FB_INIOPT_NOUPCAST          = &h00000004  '' don't allow upcasting (base types initialized from derived types)
+	FB_INIOPT_UPCAST            = &h00000008  '' allow upcasting (as used by NEW() to reset the recursion checks)
 end enum
 
 '' cProcHeader() flags