[Ada] Lib.Write: avoid use of System.Case_Util

2018-05-29  Arnaud Charlet  <charlet@adacore.com>

gcc/ada/

	* lib-writ.adb (Write_ALI): Do not use new function from s-casuti yet.
	This breaks build of cross compilers with older versions of GNAT, so
	better avoid it.

From-SVN: r260864

gcc/ada/ChangeLog

+2018-05-29  Arnaud Charlet  <charlet@adacore.com>
+
+	* lib-writ.adb (Write_ALI): Do not use new function from s-casuti yet.
+	This breaks build of cross compilers with older versions of GNAT, so
+	better avoid it.
+
 2018-05-29  Doug Rupp  <rupp@adacore.com>
 
 	* libgnarl/s-taprop.ads (Monotonic_Clock): Refine documentation to

gcc/ada/lib-writ.adb

@@ -1553,7 +1553,9 @@ package body Lib.Writ is
                --  case sensitive, the recorded file name is in lower case.
 
                if not File_Names_Case_Sensitive then
-                  Fname := Name_Find (To_Lower (Get_Name_String (Fname)));
+                  Get_Name_String (Fname);
+                  To_Lower (Name_Buffer (1 .. Name_Len));
+                  Fname := Name_Find;
                end if;
 
                Write_Info_Name_May_Be_Quoted (Fname);