[multiple changes]

2014-07-31  Robert Dewar  <dewar@adacore.com>

	* checks.ads, checks.adb (Activate_Overflow_Check): Do not set flag for
	unconstrained fpt ops.

2014-07-31  Pascal Obry  <obry@adacore.com>

	* s-fileio.adb (Open): Make sure a shared file gets inserted into
	the global list atomically. This ensures that the file descriptor
	won't be freed because another tasks is closing the file.

From-SVN: r213349

gcc/ada/ChangeLog

@@ -1,3 +1,14 @@
+2014-07-31  Robert Dewar  <dewar@adacore.com>
+
+	* checks.ads, checks.adb (Activate_Overflow_Check): Do not set flag for
+	unconstrained fpt ops.
+
+2014-07-31  Pascal Obry  <obry@adacore.com>
+
+	* s-fileio.adb (Open): Make sure a shared file gets inserted into
+	the global list atomically. This ensures that the file descriptor
+	won't be freed because another tasks is closing the file.
+
 2014-07-31  Vincent Celier  <celier@adacore.com>
 
 	* projects.texi: Minor spelling error fix.

gcc/ada/checks.adb

@@ -389,10 +389,31 @@ package body Checks is
 
    procedure Activate_Overflow_Check (N : Node_Id) is
    begin
-      if not Nkind_In (N, N_Op_Rem, N_Op_Mod, N_Op_Plus) then
-         Set_Do_Overflow_Check (N, True);
-         Possible_Local_Raise (N, Standard_Constraint_Error);
+      --  Nothing to do for unconstrained floating-point types (the test for
+      --  Etype (N) being present seems necessary in some cases, should be
+      --  tracked down, but for now just ignore the check in this case ???)
+
+      if Present (Etype (N))
+        and then Is_Floating_Point_Type (Etype (N))
+        and then not Is_Constrained (Etype (N))
+
+        --  But do the check after all if float overflow checking enforced
+
+        and then not Check_Float_Overflow
+      then
+         return;
       end if;
+
+      --  Nothing to do for Rem/Mod/Plus (overflow not possible)
+
+      if Nkind_In (N, N_Op_Rem, N_Op_Mod, N_Op_Plus) then
+         return;
+      end if;
+
+      --  Otherwise set the flag
+
+      Set_Do_Overflow_Check (N, True);
+      Possible_Local_Raise (N, Standard_Constraint_Error);
    end Activate_Overflow_Check;
 
    --------------------------

gcc/ada/checks.ads

@@ -146,7 +146,9 @@ package Checks is
    --  Always call this routine rather than calling Set_Do_Overflow_Check to
    --  set an explicit value of True, to ensure handling the local raise case.
    --  Note that this call has no effect for MOD, REM, and unary "+" for which
-   --  overflow is never possible in any case.
+   --  overflow is never possible in any case. In addition, we do not set the
+   --  flag for unconstrained floating-point type operations, since we want to
+   --  allow for the generation of IEEE infinities in such cases.
 
    procedure Activate_Range_Check (N : Node_Id);
    pragma Inline (Activate_Range_Check);

gcc/ada/s-fileio.adb

@@ -29,28 +29,26 @@
 --                                                                          --
 ------------------------------------------------------------------------------
 
-with Ada.Finalization;  use Ada.Finalization;
-with Ada.IO_Exceptions; use Ada.IO_Exceptions;
+with Ada.Finalization;           use Ada.Finalization;
+with Ada.IO_Exceptions;          use Ada.IO_Exceptions;
+with Ada.Unchecked_Deallocation;
 
 with Interfaces.C;
 with Interfaces.C_Streams; use Interfaces.C_Streams;
 
-with System.CRTL;
-
 with System.Case_Util;    use System.Case_Util;
+with System.CRTL;
 with System.OS_Lib;
 with System.Soft_Links;
 
-with Ada.Unchecked_Deallocation;
-
 package body System.File_IO is
 
    use System.File_Control_Block;
 
    package SSL renames System.Soft_Links;
 
-   use type Interfaces.C.int;
    use type CRTL.size_t;
+   use type Interfaces.C.int;
 
    subtype String_Access is System.OS_Lib.String_Access;
    procedure Free (X : in out String_Access) renames System.OS_Lib.Free;
@@ -1162,6 +1160,17 @@ package body System.File_IO is
             To_Lower (Fullname (1 .. Full_Name_Len));
          end if;
 
+         --  We need to lock all tasks from this point. This is needed as in
+         --  the case of a shared file we want to ensure that the file is
+         --  inserted into the chain with the shared status. We must be sure
+         --  that this file won't be closed (and then the runtime file
+         --  descriptor removed from the chain and released) before we leave
+         --  this routine.
+
+         --  Take a task lock to protect Open_Files
+
+         SSL.Lock_Task.all;
+
          --  If Shared=None or Shared=Yes, then check for the existence of
          --  another file with exactly the same full name.
 
@@ -1170,10 +1179,6 @@ package body System.File_IO is
                P : AFCB_Ptr;
 
             begin
-               --  Take a task lock to protect Open_Files
-
-               SSL.Lock_Task.all;
-
                --  Search list of open files
 
                P := Open_Files;
@@ -1213,13 +1218,6 @@ package body System.File_IO is
 
                   P := P.Next;
                end loop;
-
-               SSL.Unlock_Task.all;
-
-            exception
-               when others =>
-                  SSL.Unlock_Task.all;
-                  raise;
             end;
          end if;
 
@@ -1314,6 +1312,16 @@ package body System.File_IO is
 
       Chain_File (File_Ptr);
       Append_Set (File_Ptr);
+
+      --  We can now safely release the global lock, as the File_Ptr is
+      --  inserted into the global file list.
+
+      SSL.Unlock_Task.all;
+
+   exception
+      when others =>
+         SSL.Unlock_Task.all;
+         raise;
    end Open;
 
    ------------------------