[Ada] Minor tweaks for Repinfo

2018-06-11  Eric Botcazou  <ebotcazou@adacore.com>

gcc/ada/

	* gnat1drv.adb: Remove use clause for Repinfo.
	(Gnat1drv): Beef up comment about the interplay between -gnatc and
	back-end annotations.  Use full qualified name for List_Rep_Info.

From-SVN: r261420

gcc/ada/ChangeLog

+2018-06-11  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat1drv.adb: Remove use clause for Repinfo.
+	(Gnat1drv): Beef up comment about the interplay between -gnatc and
+	back-end annotations.  Use full qualified name for List_Rep_Info.
+
 2018-06-11  Hristian Kirtchev  <kirtchev@adacore.com>
 
 	* libgnat/g-arrspl.ads: Add pragma Preelaborate.

gcc/ada/gnat1drv.adb

@@ -50,7 +50,7 @@ with Osint.C;   use Osint.C;
 with Output;    use Output;
 with Par_SCO;
 with Prepcomp;
-with Repinfo;   use Repinfo;
+with Repinfo;
 with Restrict;
 with Rident;    use Rident;
 with Rtsfind;
@@ -1442,7 +1442,9 @@ begin
          Exit_Program (Ecode);
       end if;
 
-      --  In -gnatc mode, we only do annotation if -gnatt or -gnatR is also set
+      --  In -gnatc mode we only do annotation if -gnatt or -gnatR is also set,
+      --  or if -gnatwz is enabled (default setting) and there is an unchecked
+      --  conversion that involves a type whose size is not statically known,
       --  as indicated by Back_Annotate_Rep_Info being set to True.
 
       --  We don't call for annotations on a subunit, because to process those
@@ -1558,7 +1560,7 @@ begin
 
       Errout.Finalize (Last_Call => True);
       Errout.Output_Messages;
-      List_Rep_Info (Ttypes.Bytes_Big_Endian);
+      Repinfo.List_Rep_Info (Ttypes.Bytes_Big_Endian);
       Inline.List_Inlining_Info;
 
       --  Only write the library if the backend did not generate any error