[multiple changes]

2012-04-02  Robert Dewar  <dewar@adacore.com>

	* s-atopri.ads: Minor reformatting.

2012-04-02  Thomas Quinot  <quinot@adacore.com>

	* sem_util.adb: Minor reformatting, minor code cleanup.

2012-04-02  Ed Schonberg  <schonberg@adacore.com>

	* lib-xref.adb (Generate_Reference): For a reference to an
	operator symbol, set the sloc to point to the first character
	of the operator name, and not to the initial quaote.
	(Output_References): Ditto for the definition of an operator
	symbol.

2012-04-02  Vincent Celier  <celier@adacore.com>

	* ali.adb (Scan_Ali): Recognize Z lines. Set
	Implicit_With_From_Instantiation to True in the With_Record for
	Z lines.
	* ali.ads (With_Record): New Boolean component
	Implicit_With_From_Instantiation, defaulted to False.
	* csinfo.adb: Indicate that Implicit_With_From_Instantiation
	is special
	* lib-writ.adb (Write_ALI): New array Implicit_With.
	(Collect_Withs): Set Implicit_With for the unit is it is not Yes.
	(Write_With_Lines): Write a Z line instead of a W line if
	Implicit_With is Yes for the unit.
	* sem_ch12.adb (Inherit_Context): Only add a unit in the context
	if it is not there yet.
	* sinfo.ads: New flag Implicit_With_From_Instantiation (Flag12)
	added.

From-SVN: r186079

1 files changed, 25 insertions, 9 deletions

diff --git a/gcc/ada/sem_ch12.adb b/gcc/ada/sem_ch12.adb
index e516ec0..d052563 100644
--- a/gcc/ada/sem_ch12.adb
+++ b/gcc/ada/sem_ch12.adb
@@ -7761,6 +7761,9 @@ package body Sem_Ch12 is
       Item            : Node_Id;
       New_I           : Node_Id;
 
+      Clause : Node_Id;
+      OK     : Boolean;
+
    begin
       if Nkind (Parent (Gen_Decl)) = N_Compilation_Unit then
 
@@ -7782,17 +7785,30 @@ package body Sem_Ch12 is
          while Present (Item) loop
             if Nkind (Item) = N_With_Clause then
 
-               --  Take care to prevent direct cyclic with's, which can happen
-               --  if the generic body with's the current unit. Such a case
-               --  would result in binder errors (or run-time errors if the
-               --  -gnatE switch is in effect), but we want to prevent it here,
-               --  because Sem.Walk_Library_Items doesn't like cycles. Note
-               --  that we don't bother to detect indirect cycles.
+               --  Take care to prevent direct cyclic with's.
 
                if Library_Unit (Item) /= Current_Unit then
-                  New_I := New_Copy (Item);
-                  Set_Implicit_With (New_I, True);
-                  Append (New_I, Current_Context);
+                  --  Do not add a unit if it is already in the context
+
+                  Clause := First (Current_Context);
+                  OK := True;
+                  while Present (Clause) loop
+                     if Nkind (Clause) = N_With_Clause and then
+                       Chars (Name (Clause)) = Chars (Name (Item))
+                     then
+                        OK := False;
+                        exit;
+                     end if;
+
+                     Next (Clause);
+                  end loop;
+
+                  if OK then
+                     New_I := New_Copy (Item);
+                     Set_Implicit_With (New_I, True);
+                     Set_Implicit_With_From_Instantiation (New_I, True);
+                     Append (New_I, Current_Context);
+                  end if;
                end if;
             end if;