[Ada] Address potentially uninitialized variables and dead code

2020-06-02  Arnaud Charlet  <charlet@adacore.com>

gcc/ada/

	* bcheck.adb, binde.adb, bindo-diagnostics.adb, checks.adb,
	exp_aggr.adb, exp_ch3.adb, exp_ch4.adb, exp_ch7.adb,
	exp_ch9.adb, gnatname.adb, sem_case.adb, sem_ch13.adb,
	sem_ch5.adb, sem_prag.adb, sem_util.adb, uintp.adb, urealp.adb,
	xoscons.adb, xr_tabls.adb, xref_lib.adb: Initialize objects more
	explicitly and add corresponding assertions. Remove dead code.
	Also add a few Annotate pragmas to help static analysis.
	* libgnat/a-caldel.adb, libgnat/a-calend.adb,
	libgnat/a-ngcoty.adb, libgnat/a-ngelfu.adb,
	libgnat/a-ngrear.adb, libgnat/a-strfix.adb,
	libgnat/g-calend.adb, libgnat/g-catiio.adb,
	libgnat/g-comlin.adb, libgnat/g-debpoo.adb,
	libgnat/g-dirope.adb, libgnat/g-hesorg.adb,
	libgnat/g-pehage.adb, libgnat/g-socket.adb, libgnat/i-cobol.adb,
	libgnat/s-dwalin.adb, libgnat/s-dwalin.ads,
	libgnat/s-fatgen.adb, libgnat/s-gearop.adb,
	libgnat/s-genbig.adb, libgnat/s-imgrea.adb,
	libgnat/s-os_lib.adb, libgnat/s-rannum.adb,
	libgnat/s-regpat.adb, libgnat/s-trasym__dwarf.adb,
	libgnat/s-valrea.adb: Ditto.

26 files changed, 116 insertions, 51 deletions

diff --git a/gcc/ada/libgnat/a-caldel.adb b/gcc/ada/libgnat/a-caldel.adb
index b7cfefc..9244425 100644
--- a/gcc/ada/libgnat/a-caldel.adb
+++ b/gcc/ada/libgnat/a-caldel.adb
@@ -103,6 +103,8 @@ begin
    --  this soft link, or this will be overridden during the elaboration of
    --  System.Tasking.Initialization
 
+   pragma Annotate (CodePeer, Modified, SSL.Timed_Delay);
+
    if SSL.Timed_Delay = null then
       SSL.Timed_Delay := Timed_Delay_NT'Access;
    end if;
diff --git a/gcc/ada/libgnat/a-calend.adb b/gcc/ada/libgnat/a-calend.adb
index 4cbfeff..219fd9a 100644
--- a/gcc/ada/libgnat/a-calend.adb
+++ b/gcc/ada/libgnat/a-calend.adb
@@ -435,18 +435,14 @@ is
       if End_T < Leap_Second_Times (1) then
          Elapsed_Leaps := 0;
          Next_Leap     := Leap_Second_Times (1);
-         return;
 
       elsif Start_T > Leap_Second_Times (Leap_Seconds_Count) then
          Elapsed_Leaps := 0;
          Next_Leap     := End_Of_Time;
-         return;
-      end if;
-
-      --  Perform the calculations only if the start date is within the leap
-      --  second occurrences table.
 
-      if Start_T <= Leap_Second_Times (Leap_Seconds_Count) then
+      else
+         --  Perform the calculations only if the start date is within the leap
+         --  second occurrences table.
 
          --    1    2                  N - 1   N
          --  +----+----+--  . . .  --+-------+---+
@@ -480,9 +476,6 @@ is
          end if;
 
          Elapsed_Leaps := End_Index - Start_Index;
-
-      else
-         Elapsed_Leaps := 0;
       end if;
    end Cumulative_Leap_Seconds;
 
@@ -763,6 +756,7 @@ is
         (Secs_T'Unchecked_Access,
          Flag'Unchecked_Access,
          Offset'Unchecked_Access);
+      pragma Annotate (CodePeer, Modified, Offset);
 
       return Long_Integer (Offset);
    end UTC_Time_Offset;
diff --git a/gcc/ada/libgnat/a-ngcoty.adb b/gcc/ada/libgnat/a-ngcoty.adb
index bece703..deb200b 100644
--- a/gcc/ada/libgnat/a-ngcoty.adb
+++ b/gcc/ada/libgnat/a-ngcoty.adb
@@ -66,11 +66,19 @@ package body Ada.Numerics.Generic_Complex_Types is
          --  return false, the test can only be written thus.
 
          if not (abs (X) <= R'Last) then
+            pragma Annotate
+              (CodePeer, Intentional,
+               "test always false", "test for infinity");
+
             X := Scale**2 * ((Left.Re / Scale) * (Right.Re / Scale) -
                              (Left.Im / Scale) * (Right.Im / Scale));
          end if;
 
          if not (abs (Y) <= R'Last) then
+            pragma Annotate
+              (CodePeer, Intentional,
+               "test always false", "test for infinity");
+
             Y := Scale**2 * ((Left.Re / Scale) * (Right.Im / Scale)
                            + (Left.Im / Scale) * (Right.Re / Scale));
          end if;
@@ -588,6 +596,7 @@ package body Ada.Numerics.Generic_Complex_Types is
 
       exception
          when Constraint_Error =>
+            pragma Assert (X.Re /= 0.0);
             return R (Double (abs (X.Re))
               * Sqrt (1.0 + (Double (X.Im) / Double (X.Re)) ** 2));
       end;
@@ -602,6 +611,7 @@ package body Ada.Numerics.Generic_Complex_Types is
 
       exception
          when Constraint_Error =>
+            pragma Assert (X.Im /= 0.0);
             return R (Double (abs (X.Im))
               * Sqrt (1.0 + (Double (X.Re) / Double (X.Im)) ** 2));
       end;
diff --git a/gcc/ada/libgnat/a-ngelfu.adb b/gcc/ada/libgnat/a-ngelfu.adb
index 71cd47b..3d49404 100644
--- a/gcc/ada/libgnat/a-ngelfu.adb
+++ b/gcc/ada/libgnat/a-ngelfu.adb
@@ -680,6 +680,8 @@ is
       Z := G * G;
       P := G * ((P2 * Z + P1) * Z + P0);
       Q := ((Q3 * Z + Q2) * Z + Q1) * Z + Q0;
+
+      pragma Assert (Q /= P);
       R := 0.5 + P / (Q - P);
 
       R := Float_Type'Base'Scaling (R, Integer (XN) + 1);
diff --git a/gcc/ada/libgnat/a-ngrear.adb b/gcc/ada/libgnat/a-ngrear.adb
index 8418ec1..8348cb7 100644
--- a/gcc/ada/libgnat/a-ngrear.adb
+++ b/gcc/ada/libgnat/a-ngrear.adb
@@ -560,6 +560,8 @@ package body Ada.Numerics.Generic_Real_Arrays is
       function Compute_Tan (P, H : Real) return Real is
          (if Is_Tiny (P, Compared_To => H) then P / H
           else Compute_Tan (Theta => H / (2.0 * P)));
+      pragma Annotate
+        (CodePeer, False_Positive, "divide by zero", "H, P /= 0");
 
       function Sum_Strict_Upper (M : Square_Matrix) return Real;
       --  Return the sum of all elements in the strict upper triangle of M
diff --git a/gcc/ada/libgnat/a-strfix.adb b/gcc/ada/libgnat/a-strfix.adb
index b8b5f42..1f94b86 100644
--- a/gcc/ada/libgnat/a-strfix.adb
+++ b/gcc/ada/libgnat/a-strfix.adb
@@ -192,6 +192,10 @@ package body Ada.Strings.Fixed is
       elsif From not in Source'Range
         or else Through > Source'Last
       then
+         pragma Annotate
+           (CodePeer, False_Positive,
+            "test always false", "self fullfilling prophecy");
+
          --  In most cases this raises an exception, but the case of deleting
          --  a null string at the end of the current one is a special-case, and
          --  reflects the equivalence with Replace_String (RM A.4.3 (86/3)).
diff --git a/gcc/ada/libgnat/g-calend.adb b/gcc/ada/libgnat/g-calend.adb
index d1d4b55..ab5bab3 100644
--- a/gcc/ada/libgnat/g-calend.adb
+++ b/gcc/ada/libgnat/g-calend.adb
@@ -352,6 +352,9 @@ package body GNAT.Calendar is
 
    begin
       timeval_to_duration (T, sec'Access, usec'Access);
+      pragma Annotate (CodePeer, Modified, sec);
+      pragma Annotate (CodePeer, Modified, usec);
+
       return Duration (sec) + Duration (usec) / Micro;
    end To_Duration;
 
diff --git a/gcc/ada/libgnat/g-catiio.adb b/gcc/ada/libgnat/g-catiio.adb
index dc2fa40..cc860ab 100644
--- a/gcc/ada/libgnat/g-catiio.adb
+++ b/gcc/ada/libgnat/g-catiio.adb
@@ -950,6 +950,8 @@ package body GNAT.Calendar.Time_IO is
       when End_Of_Source_Reached
          | Wrong_Syntax
       =>
+         Time :=
+           Time_Of (Year_Number'First, Month_Number'First, Day_Number'First);
          Success := False;
    end Parse_ISO_8861_UTC;
 
diff --git a/gcc/ada/libgnat/g-comlin.adb b/gcc/ada/libgnat/g-comlin.adb
index ec057a9..bb553e9 100644
--- a/gcc/ada/libgnat/g-comlin.adb
+++ b/gcc/ada/libgnat/g-comlin.adb
@@ -537,6 +537,7 @@ package body GNAT.Command_Line is
       P      : Switch_Parameter_Type;
 
    begin
+      Param             := Parameter_None;
       Index_In_Switches := 0;
       Switch_Length     := 0;
 
diff --git a/gcc/ada/libgnat/g-debpoo.adb b/gcc/ada/libgnat/g-debpoo.adb
index 52c0c50..ae2fb1c 100644
--- a/gcc/ada/libgnat/g-debpoo.adb
+++ b/gcc/ada/libgnat/g-debpoo.adb
@@ -1420,6 +1420,7 @@ package body GNAT.Debug_Pools is
 
    begin
       Valid := Is_Valid (Storage_Address);
+      Size_In_Storage_Elements := Storage_Count'First;
 
       if Is_Valid (Storage_Address) then
          declare
diff --git a/gcc/ada/libgnat/g-dirope.adb b/gcc/ada/libgnat/g-dirope.adb
index 9153c70..0fd7a24 100644
--- a/gcc/ada/libgnat/g-dirope.adb
+++ b/gcc/ada/libgnat/g-dirope.adb
@@ -352,6 +352,8 @@ package body GNAT.Directory_Operations is
       begin
          K := K + 1;
 
+         pragma Annotate (CodePeer, Modified, P);
+
          if P = '%' or else Path (K) = '{' then
 
             --  Set terminator character
diff --git a/gcc/ada/libgnat/g-hesorg.adb b/gcc/ada/libgnat/g-hesorg.adb
index fec6e9c..bf54874 100644
--- a/gcc/ada/libgnat/g-hesorg.adb
+++ b/gcc/ada/libgnat/g-hesorg.adb
@@ -45,6 +45,8 @@ package body GNAT.Heap_Sort_G is
    --  from 2NlogN to NlogN.
 
    procedure Sort (N : Natural) is
+      pragma Annotate (CodePeer, Skip_Analysis);
+      --  CodePeer is sometimes getting confused on this procedure
 
       Max : Natural := N;
       --  Current Max index in tree being sifted
diff --git a/gcc/ada/libgnat/g-pehage.adb b/gcc/ada/libgnat/g-pehage.adb
index 9b88256..a65dc85 100644
--- a/gcc/ada/libgnat/g-pehage.adb
+++ b/gcc/ada/libgnat/g-pehage.adb
@@ -622,6 +622,7 @@ package body GNAT.Perfect_Hash_Generators is
             E := Get_Edges (J);
 
             if Get_Graph (E.Y) = -1 then
+               pragma Assert (NK /= 0);
                Set_Graph (E.Y, (E.Key - Get_Graph (X)) mod NK);
                Assign (E.Y);
             end if;
@@ -2201,6 +2202,8 @@ package body GNAT.Perfect_Hash_Generators is
          --  in the position selection.
 
          for J in S'Range loop
+            pragma Annotate (CodePeer, Modified, S (J));
+
             if S (J).First = S (J).Last then
                F := S (J).First;
                L := S (J).Last;
@@ -2359,6 +2362,10 @@ package body GNAT.Perfect_Hash_Generators is
 
             for P in 1 .. Last_Sel_Pos - 1 loop
                if Max_Diff_Sel_Pos < Sel_Position (P) then
+                  pragma Annotate
+                    (CodePeer, False_Positive,
+                     "test always false", "false positive?");
+
                   Sel_Position (P + 1 .. Last_Sel_Pos) :=
                     Sel_Position (P .. Last_Sel_Pos - 1);
                   Sel_Position (P) := Max_Diff_Sel_Pos;
@@ -2525,6 +2532,7 @@ package body GNAT.Perfect_Hash_Generators is
             for J in 0 .. T1_Len - 1 loop
                exit when Word (J + 1) = ASCII.NUL;
                R := Get_Table (Table, J, Get_Used_Char (Word (J + 1)));
+               pragma Assert (NV /= 0);
                S := (S + R) mod NV;
             end loop;
 
@@ -2532,6 +2540,7 @@ package body GNAT.Perfect_Hash_Generators is
             for J in 0 .. T1_Len - 1 loop
                exit when Word (J + 1) = ASCII.NUL;
                R := Get_Table (Table, J, 0);
+               pragma Assert (NV /= 0);
                S := (S + R * Character'Pos (Word (J + 1))) mod NV;
             end loop;
       end case;
diff --git a/gcc/ada/libgnat/g-socket.adb b/gcc/ada/libgnat/g-socket.adb
index 6c65424..8f8c9d81 100644
--- a/gcc/ada/libgnat/g-socket.adb
+++ b/gcc/ada/libgnat/g-socket.adb
@@ -836,6 +836,7 @@ package body GNAT.Sockets is
       --  the waiting task to resume its execution.
 
       Res := Signalling_Fds.Create (Two_Fds'Access);
+      pragma Annotate (CodePeer, Modified, Two_Fds);
 
       if Res = Failure then
          Raise_Socket_Error (Socket_Errno);
@@ -886,6 +887,7 @@ package body GNAT.Sockets is
         ((if Family = Family_Unspec then Default_Socket_Pair_Family
           else Families (Family)),
          Modes (Mode), Levels (Level), Pair'Access);
+      pragma Annotate (CodePeer, Modified, Pair);
 
       if Res = Failure then
          Raise_Socket_Error (Socket_Errno);
@@ -957,8 +959,12 @@ package body GNAT.Sockets is
       if Item.Last /= No_Socket then
          Get_Socket_From_Set
            (Item.Set'Access, Last => L'Access, Socket => S'Access);
+         pragma Annotate (CodePeer, Modified, L);
+         pragma Annotate (CodePeer, Modified, S);
+
          Item.Last := Socket_Type (L);
          Socket    := Socket_Type (S);
+
       else
          Socket := No_Socket;
       end if;
@@ -2921,8 +2927,7 @@ package body GNAT.Sockets is
    -- To_Int --
    ------------
 
-   function To_Int (F : Request_Flag_Type) return C.int
-   is
+   function To_Int (F : Request_Flag_Type) return C.int is
       Current : Request_Flag_Type := F;
       Result  : C.int := 0;
 
@@ -2932,6 +2937,10 @@ package body GNAT.Sockets is
 
          if Current mod 2 /= 0 then
             if Flags (J) = -1 then
+               pragma Annotate
+                 (CodePeer, False_Positive,
+                  "test always false", "self fulfilling prophecy");
+
                Raise_Socket_Error (SOSC.EOPNOTSUPP);
             end if;
 
diff --git a/gcc/ada/libgnat/i-cobol.adb b/gcc/ada/libgnat/i-cobol.adb
index 807a3a1..6caa351 100644
--- a/gcc/ada/libgnat/i-cobol.adb
+++ b/gcc/ada/libgnat/i-cobol.adb
@@ -240,11 +240,6 @@ package body Interfaces.COBOL is
                            (COBOL_Character'Pos (K) -
                              COBOL_Character'Pos (COBOL_Digits'First));
 
-            elsif K in COBOL_Plus_Digits then
-               Result := Result * 10 +
-                           (COBOL_Character'Pos (K) -
-                             COBOL_Character'Pos (COBOL_Plus_Digits'First));
-
             elsif K in COBOL_Minus_Digits then
                Result := Result * 10 +
                            (COBOL_Character'Pos (K) -
diff --git a/gcc/ada/libgnat/s-dwalin.adb b/gcc/ada/libgnat/s-dwalin.adb
index 5307eae..6745953 100644
--- a/gcc/ada/libgnat/s-dwalin.adb
+++ b/gcc/ada/libgnat/s-dwalin.adb
@@ -440,6 +440,10 @@ package body System.Dwarf_Lines is
         or else Info_Sec = Null_Section
         or else Aranges_Sec = Null_Section
       then
+         pragma Annotate
+           (CodePeer, False_Positive,
+            "test always true", "codepeer got confused");
+
          C.Has_Debug := False;
          return;
       end if;
@@ -883,6 +887,7 @@ package body System.Dwarf_Lines is
       Success     :    out Boolean)
    is
    begin
+      Info_Offset := 0;
       Seek (C.Aranges, 0);
 
       while Tell (C.Aranges) < Length (C.Aranges) loop
@@ -905,6 +910,7 @@ package body System.Dwarf_Lines is
             end;
          end loop;
       end loop;
+
       Success := False;
    end Aranges_Lookup;
 
@@ -1028,6 +1034,7 @@ package body System.Dwarf_Lines is
       Has_Child     : uint8;
       pragma Unreferenced (Has_Child);
    begin
+      Line_Offset := 0;
       Success := False;
 
       Seek (C.Info, Info_Offset);
@@ -1119,7 +1126,8 @@ package body System.Dwarf_Lines is
       Version     : uint16;
       Sz          : uint8;
    begin
-      Success := False;
+      Success     := False;
+      Info_Offset := 0;
 
       Read_Initial_Length (C.Aranges, Unit_Length, Is64);
 
@@ -1407,6 +1415,7 @@ package body System.Dwarf_Lines is
       Success      : Boolean;
       Done         : Boolean;
       S            : Object_Symbol;
+
    begin
       --  Initialize result
       Dir_Name    := null;
@@ -1422,6 +1431,8 @@ package body System.Dwarf_Lines is
          begin
             First := C.Cache'First;
             Last  := C.Cache'Last;
+            Mid   := First;
+
             while First <= Last loop
                Mid := First + (Last - First) / 2;
                if Addr_Off < C.Cache (Mid).First then
@@ -1432,6 +1443,7 @@ package body System.Dwarf_Lines is
                   exit;
                end if;
             end loop;
+
             if Addr_Off >= C.Cache (Mid).First
               and then Addr_Off < C.Cache (Mid).First + C.Cache (Mid).Size
             then
@@ -1474,6 +1486,7 @@ package body System.Dwarf_Lines is
       C.Next_Prologue := 0;
       Initialize_State_Machine (C);
       Parse_Prologue (C);
+      Previous_Row.Line := 0;
 
       --  Advance to the first entry
 
@@ -1535,7 +1548,7 @@ package body System.Dwarf_Lines is
      (Cin          :        Dwarf_Context;
       Traceback    :        AET.Tracebacks_Array;
       Suppress_Hex :        Boolean;
-      Symbol_Found : in out Boolean;
+      Symbol_Found :    out Boolean;
       Res          : in out System.Bounded_Strings.Bounded_String)
    is
       use Ada.Characters.Handling;
diff --git a/gcc/ada/libgnat/s-dwalin.ads b/gcc/ada/libgnat/s-dwalin.ads
index 297fd8e..cfde1c6 100644
--- a/gcc/ada/libgnat/s-dwalin.ads
+++ b/gcc/ada/libgnat/s-dwalin.ads
@@ -93,7 +93,7 @@ package System.Dwarf_Lines is
      (Cin          :        Dwarf_Context;
       Traceback    :        AET.Tracebacks_Array;
       Suppress_Hex :        Boolean;
-      Symbol_Found : in out Boolean;
+      Symbol_Found :    out Boolean;
       Res          : in out System.Bounded_Strings.Bounded_String);
    --  Generate a string for a traceback suitable for displaying to the user.
    --  If one or more symbols are found, Symbol_Found is set to True. This
diff --git a/gcc/ada/libgnat/s-fatgen.adb b/gcc/ada/libgnat/s-fatgen.adb
index 93237fb..481d672 100644
--- a/gcc/ada/libgnat/s-fatgen.adb
+++ b/gcc/ada/libgnat/s-fatgen.adb
@@ -219,6 +219,10 @@ package body System.Fat_Gen is
                   Ax := Ax * R_Power (Expbits'Last);
                   Ex := Ex - Log_Power (Expbits'Last);
                end loop;
+               pragma Annotate
+                 (CodePeer, Intentional,
+                  "test always false",
+                  "expected for some instantiations");
 
                --  Rad ** -64 <= Ax < 1
 
diff --git a/gcc/ada/libgnat/s-gearop.adb b/gcc/ada/libgnat/s-gearop.adb
index 4064571..166b04b 100644
--- a/gcc/ada/libgnat/s-gearop.adb
+++ b/gcc/ada/libgnat/s-gearop.adb
@@ -240,6 +240,8 @@ package body System.Generic_Array_Operations is
          for J in N'Range (2) loop
             N (Row - M'First (1) + N'First (1), J) :=
               N (Row - M'First (1) + N'First (1), J) / Scale;
+            pragma Annotate
+              (CodePeer, False_Positive, "divide by zero", "Scale /= 0");
          end loop;
       end Divide_Row;
 
@@ -602,6 +604,9 @@ package body System.Generic_Array_Operations is
          end if;
 
       elsif X > Real'Base'Last then
+         pragma Annotate
+           (CodePeer, Intentional,
+            "test always false", "test for infinity");
 
          --  X is infinity, which is its own square root
 
@@ -627,6 +632,8 @@ package body System.Generic_Array_Operations is
       --  of precision.
 
       for J in 1 .. 8 loop
+         pragma Assert (Root /= 0.0);
+
          Next := (Root + X / Root) / 2.0;
          exit when Root = Next;
          Root := Next;
diff --git a/gcc/ada/libgnat/s-genbig.adb b/gcc/ada/libgnat/s-genbig.adb
index 0a92dfb..69d284f 100644
--- a/gcc/ada/libgnat/s-genbig.adb
+++ b/gcc/ada/libgnat/s-genbig.adb
@@ -733,6 +733,7 @@ package body System.Generic_Bignums is
             ND := 0;
             for J in 1 .. X.Len loop
                ND := Base * ND + DD (X.D (J));
+               pragma Assert (Div /= 0);
                Result (J) := SD (ND / Div);
                ND := ND rem Div;
             end loop;
diff --git a/gcc/ada/libgnat/s-imgrea.adb b/gcc/ada/libgnat/s-imgrea.adb
index 467c482..46cacd0 100644
--- a/gcc/ada/libgnat/s-imgrea.adb
+++ b/gcc/ada/libgnat/s-imgrea.adb
@@ -289,6 +289,8 @@ package body System.Img_Real is
             --  What we are looking for is a power of ten to divide X by
             --  so that the result lies within the required range.
 
+            pragma Assert (Powten (Maxpow) /= 0.0);
+
             loop
                XP := X / Powten (Maxpow);
                exit when XP < Powten (S) or else Scale > Maxscaling;
@@ -490,6 +492,9 @@ package body System.Img_Real is
          --  an infinite value, so we print Inf.
 
          if V > Long_Long_Float'Last then
+            pragma Annotate
+              (CodePeer, Intentional, "test always true", "test for infinity");
+
             Set ('+');
             Set ('I');
             Set ('n');
diff --git a/gcc/ada/libgnat/s-os_lib.adb b/gcc/ada/libgnat/s-os_lib.adb
index 258cd64..28fbbf3 100644
--- a/gcc/ada/libgnat/s-os_lib.adb
+++ b/gcc/ada/libgnat/s-os_lib.adb
@@ -574,14 +574,15 @@ package body System.OS_Lib is
                --  touch destination file at all.
 
                From := Open_Read (Name, Binary);
-               if From /= Invalid_FD then
+
+               if From = Invalid_FD then
+                  Success := False;
+               else
                   To := Open_Read_Write (Pathname, Binary);
+                  Lseek (To, 0, Seek_End);
+                  Copy (From, To);
                end if;
 
-               Lseek (To, 0, Seek_End);
-
-               Copy (From, To);
-
             --  Appending to directory, not allowed
 
             elsif Is_Directory (Pathname) then
@@ -1999,6 +2000,8 @@ package body System.OS_Lib is
 
                   --  If the string ends with \, double it
 
+                  pragma Annotate (CodePeer, Modified, Res (J - 1));
+
                   if Res (J - 1) = '\' then
                      Res (J) := '\';
                      J := J + 1;
diff --git a/gcc/ada/libgnat/s-rannum.adb b/gcc/ada/libgnat/s-rannum.adb
index 0590313..1aa755c 100644
--- a/gcc/ada/libgnat/s-rannum.adb
+++ b/gcc/ada/libgnat/s-rannum.adb
@@ -295,6 +295,7 @@ is
             K      : Bit_Count;       --  Next decrement to exponent
 
          begin
+            K := 0;
             Mantissa := Random (Gen) / 2**Extra_Bits;
             R := Unsigned_32 (Mantissa mod 2**Extra_Bits);
             R_Bits := Extra_Bits;
diff --git a/gcc/ada/libgnat/s-regpat.adb b/gcc/ada/libgnat/s-regpat.adb
index ae69f47..69fe150 100644
--- a/gcc/ada/libgnat/s-regpat.adb
+++ b/gcc/ada/libgnat/s-regpat.adb
@@ -1460,19 +1460,9 @@ package body System.Regpat is
                  and then Expression (Parse_Pos + 1) /= ']'
                then
                   Parse_Pos := Parse_Pos + 1;
-
-                  --  Do we have a range like '\d-a' and '[:space:]-a'
-                  --  which is not a real range
-
-                  if Named_Class /= ANYOF_NONE then
-                     Set_In_Class (Bitmap, '-');
-                  else
-                     In_Range := True;
-                  end if;
-
+                  In_Range := True;
                else
                   Set_In_Class (Bitmap, Value);
-
                end if;
 
             --  Else in a character range
@@ -3275,13 +3265,13 @@ package body System.Regpat is
         (IP  : Pointer;
          Max : Natural := Natural'Last) return Natural
       is
-         Scan  : Natural := Input_Pos;
-         Last  : Natural;
-         Op    : constant Opcode := Opcode'Val (Character'Pos (Program (IP)));
-         Count : Natural;
-         C     : Character;
-         Is_First : Boolean := True;
-         Bitmap   : Character_Class;
+         Scan   : Natural := Input_Pos;
+         Last   : Natural;
+         Op     : constant Opcode :=
+           Opcode'Val (Character'Pos (Program (IP)));
+         Count  : Natural;
+         C      : Character;
+         Bitmap : Character_Class;
 
       begin
          if Max = Natural'Last or else Scan + Max - 1 > Last_In_Data then
@@ -3324,10 +3314,7 @@ package body System.Regpat is
                end loop;
 
             when ANYOF =>
-               if Is_First then
-                  Bitmap_Operand (Program, IP, Bitmap);
-                  Is_First := False;
-               end if;
+               Bitmap_Operand (Program, IP, Bitmap);
 
                while Scan <= Last
                  and then Get_From_Class (Bitmap, Data (Scan))
diff --git a/gcc/ada/libgnat/s-trasym__dwarf.adb b/gcc/ada/libgnat/s-trasym__dwarf.adb
index b116a10..9f96275 100644
--- a/gcc/ada/libgnat/s-trasym__dwarf.adb
+++ b/gcc/ada/libgnat/s-trasym__dwarf.adb
@@ -438,7 +438,7 @@ package body System.Traceback.Symbolic is
       Suppress_Hex :        Boolean;
       Res          : in out Bounded_String)
    is
-      Success : Boolean := False;
+      Success : Boolean;
    begin
       if Symbolic.Module_Name.Is_Supported then
          Append (Res, '[');
diff --git a/gcc/ada/libgnat/s-valrea.adb b/gcc/ada/libgnat/s-valrea.adb
index 424ccd0..2ecc99b 100644
--- a/gcc/ada/libgnat/s-valrea.adb
+++ b/gcc/ada/libgnat/s-valrea.adb
@@ -92,8 +92,7 @@ package body System.Val_Real is
    -- As_Digit --
    --------------
 
-   function As_Digit (C : Character) return Char_As_Digit
-   is
+   function As_Digit (C : Character) return Char_As_Digit is
    begin
       case C is
          when '0' .. '9' =>
@@ -133,7 +132,9 @@ package body System.Val_Real is
 
       Trailing_Zeros : Natural := 0;
       --  Number of trailing zeros at a given point.
+
    begin
+      pragma Assert (Base in 2 .. 16);
 
       --  If initial Scale is not 0 then it means that Precision_Limit was
       --  reached during integral part scanning.
@@ -217,7 +218,6 @@ package body System.Val_Real is
             end if;
          end if;
       end loop;
-
    end Scan_Decimal_Digits;
 
    --------------------------
@@ -268,6 +268,8 @@ package body System.Val_Real is
             --  Precision limit has been reached so just update the exponent
             Scale := Scale + 1;
          else
+            pragma Assert (Base /= 0);
+
             if Value > (Precision_Limit - Digit) / Base then
                --  Updating Value will overflow so ignore this digit and any
                --  following ones. Only update the scale
@@ -369,6 +371,10 @@ package body System.Val_Real is
 
       --  First character can be either a decimal digit or a dot.
       if Str (Index) in '0' .. '9' then
+         pragma Annotate
+           (CodePeer, Intentional,
+            "test always true", "defensive code below");
+
          --  If this is a digit it can indicates either the float decimal
          --  part or the base to use
          Scan_Integral_Digits