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Description: [Ada] New Repinfo.Input unit to read back JSON representation info.
 ASIS/GPL-2019 depends on repinfo-input.ad[bs] from gnat_util/GPL-2019.
 gnat_utils/GPL-2019 duplicates sources from GCC/GPL-2019.
 .
 In Debian, we avoid code duplication and build gnat_util directly
 from GCC-9 sources (under the name gnatvsn for historical reasons).
 .
 repinfo-input exists in GCC/GPL-2019 but not yet in GCC/9,
 so we cherry-pick the upstream commit introducing it.
Origin: https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=5dc190e5b8095871578958225d5c4ad515417576

--- a/src/gcc/ada/alloc.ads
+++ b/src/gcc/ada/alloc.ads
@@ -116,6 +116,9 @@
    Rep_Table_Initial                : constant := 1000;       -- Repinfo
    Rep_Table_Increment              : constant := 200;
 
+   Rep_JSON_Table_Initial           : constant := 10;          -- Repinfo
+   Rep_JSON_Table_Increment         : constant := 200;
+
    Scope_Stack_Initial              : constant := 10;         -- Sem
    Scope_Stack_Increment            : constant := 200;
 
--- a/src/gcc/ada/debug.adb
+++ b/src/gcc/ada/debug.adb
@@ -154,7 +154,7 @@
    --  d_g
    --  d_h
    --  d_i  Ignore activations and calls to instances for elaboration
-   --  d_j
+   --  d_j  Read JSON files and populate Repinfo tables (opposite of -gnatRjs)
    --  d_k
    --  d_l
    --  d_m
@@ -988,6 +988,10 @@
    --       subprogram or task type defined in an external instance for both
    --       the static and dynamic elaboration models.
 
+   --  d_j  The compiler reads JSON files that would be generated by the same
+   --       compilation session if -gnatRjs was passed, in order to populate
+   --       the internal tables of the Repinfo unit from them.
+
    --  d_p  The compiler ignores calls to subprograms which verify the run-time
    --       semantics of invariants and postconditions in both the static and
    --       dynamic elaboration models.
--- a/src/gcc/ada/gcc-interface/Make-lang.in
+++ b/src/gcc/ada/gcc-interface/Make-lang.in
@@ -355,6 +355,7 @@
  ada/prep.o	\
  ada/prepcomp.o	\
  ada/put_scos.o	\
+ ada/repinfo-input.o	\
  ada/repinfo.o	\
  ada/restrict.o	\
  ada/rident.o	\
--- a/src/gcc/ada/gnat1drv.adb
+++ b/src/gcc/ada/gnat1drv.adb
@@ -51,6 +51,7 @@
 with Par_SCO;
 with Prepcomp;
 with Repinfo;
+with Repinfo.Input;
 with Restrict;
 with Rident;    use Rident;
 with Rtsfind;
@@ -66,6 +67,7 @@
 with Sem_Type;
 with Set_Targ;
 with Sinfo;     use Sinfo;
+with Sinput;    use Sinput;
 with Sinput.L;  use Sinput.L;
 with Snames;    use Snames;
 with Sprint;    use Sprint;
@@ -114,6 +116,12 @@
    --  the information provided by the back end in back annotation of declared
    --  entities (e.g. actual size and alignment values chosen by the back end).
 
+   procedure Read_JSON_Files_For_Repinfo;
+   --  This procedure exercises the JSON parser of Repinfo by reading back the
+   --  JSON files generated by -gnatRjs in a previous compilation session. It
+   --  is intended to make sure that the JSON generator and the JSON parser are
+   --  kept synchronized when the JSON format evolves.
+
    ----------------------------
    -- Adjust_Global_Switches --
    ----------------------------
@@ -1037,6 +1045,38 @@ procedure Gnat1drv is
       --  end if;
    end Post_Compilation_Validation_Checks;
 
+   -----------------------------------
+   --  Read_JSON_Files_For_Repinfo  --
+   -----------------------------------
+
+   procedure Read_JSON_Files_For_Repinfo is
+   begin
+      --  This is the same loop construct as in Repinfo.List_Rep_Info
+
+      for U in Main_Unit .. Last_Unit loop
+         if In_Extended_Main_Source_Unit (Cunit_Entity (U)) then
+            declare
+               Nam : constant String :=
+                     Get_Name_String (File_Name (Source_Index (U))) & ".json";
+               Namid : constant File_Name_Type := Name_Enter (Nam);
+               Index : constant Source_File_Index := Load_Config_File (Namid);
+
+            begin
+               if Index = No_Source_File then
+                  Write_Str ("cannot locate ");
+                  Write_Line (Nam);
+                  raise Unrecoverable_Error;
+               end if;
+
+               Repinfo.Input.Read_JSON_Stream (Source_Text (Index).all, Nam);
+            exception
+               when Repinfo.Input.Invalid_JSON_Stream =>
+                  raise Unrecoverable_Error;
+            end;
+         end if;
+      end loop;
+   end Read_JSON_Files_For_Repinfo;
+
    --  Local variables
 
    Back_End_Mode : Back_End.Back_End_Mode_Type;
@@ -1103,7 +1143,6 @@ begin
          --  Acquire target parameters from system.ads (package System source)
 
          Targparm_Acquire : declare
-            use Sinput;
 
             S : Source_File_Index;
             N : File_Name_Type;
@@ -1571,6 +1610,12 @@ begin
          Par_SCO.SCO_Record_Filtered;
       end if;
 
+      --  If -gnatd_j is specified, exercise the JSON parser of Repinfo
+
+      if Debug_Flag_Underscore_J then
+         Read_JSON_Files_For_Repinfo;
+      end if;
+
       --  Back end needs to explicitly unlock tables it needs to touch
 
       Atree.Lock;
--- /dev/null
+++ b/src/gcc/ada/repinfo-input.adb
@@ -0,0 +1,1350 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                         R E P I N F O - I N P U T                        --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--          Copyright (C) 2018-2019, Free Software Foundation, Inc.         --
+--                                                                          --
+-- GNAT is free software;  you can  redistribute it  and/or modify it under --
+-- terms of the  GNU General Public License as published  by the Free Soft- --
+-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
+-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
+-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
+-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
+--                                                                          --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception,   --
+-- version 3.1, as published by the Free Software Foundation.               --
+--                                                                          --
+-- You should have received a copy of the GNU General Public License and    --
+-- a copy of the GCC Runtime Library Exception along with this program;     --
+-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
+-- <http://www.gnu.org/licenses/>.                                          --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+with Alloc;
+with Csets;    use Csets;
+with Hostparm; use Hostparm;
+with Namet;    use Namet;
+with Output;   use Output;
+with Snames;   use Snames;
+with Table;
+
+package body Repinfo.Input is
+
+   SSU : constant := 8;
+   --  Value for Storage_Unit, we do not want to get this from TTypes, since
+   --  this introduces problematic dependencies in ASIS, and in any case this
+   --  value is assumed to be 8 for the implementation of the DDA.
+
+   type JSON_Entity_Kind is (JE_Record_Type, JE_Array_Type, JE_Other);
+   --  Kind of an entiy
+
+   type JSON_Entity_Node (Kind : JSON_Entity_Kind := JE_Other) is record
+      Esize   : Node_Ref_Or_Val;
+      RM_Size : Node_Ref_Or_Val;
+      case Kind is
+         when JE_Record_Type => Variant        : Nat;
+         when JE_Array_Type  => Component_Size : Node_Ref_Or_Val;
+         when JE_Other       => Dummy          : Boolean;
+      end case;
+   end record;
+   pragma Unchecked_Union (JSON_Entity_Node);
+   --  Record to represent an entity
+
+   package JSON_Entity_Table is new Table.Table (
+      Table_Component_Type => JSON_Entity_Node,
+      Table_Index_Type     => Nat,
+      Table_Low_Bound      => 1,
+      Table_Initial        => Alloc.Rep_JSON_Table_Initial,
+      Table_Increment      => Alloc.Rep_JSON_Table_Increment,
+      Table_Name           => "JSON_Entity_Table");
+   --  Table of entities
+
+   type JSON_Component_Node is record
+      Bit_Offset : Node_Ref_Or_Val;
+      Esize      : Node_Ref_Or_Val;
+   end record;
+   --  Record to represent a component
+
+   package JSON_Component_Table is new Table.Table (
+      Table_Component_Type => JSON_Component_Node,
+      Table_Index_Type     => Nat,
+      Table_Low_Bound      => 1,
+      Table_Initial        => Alloc.Rep_JSON_Table_Initial,
+      Table_Increment      => Alloc.Rep_JSON_Table_Increment,
+      Table_Name           => "JSON_Component_Table");
+   --  Table of components
+
+   type JSON_Variant_Node is record
+      Present : Node_Ref_Or_Val;
+      Variant : Nat;
+      Next    : Nat;
+   end record;
+   --  Record to represent a variant
+
+   package JSON_Variant_Table is new Table.Table (
+      Table_Component_Type => JSON_Variant_Node,
+      Table_Index_Type     => Nat,
+      Table_Low_Bound      => 1,
+      Table_Initial        => Alloc.Rep_JSON_Table_Initial,
+      Table_Increment      => Alloc.Rep_JSON_Table_Increment,
+      Table_Name           => "JSON_Variant_Table");
+   --  Table of variants
+
+   -------------------------------------
+   --  Get_JSON_Component_Bit_Offset  --
+   -------------------------------------
+
+   function Get_JSON_Component_Bit_Offset
+     (Name        : String;
+      Record_Name : String) return Node_Ref_Or_Val
+   is
+      Namid : constant Valid_Name_Id := Name_Find (Record_Name & '.' & Name);
+      Index : constant Int := Get_Name_Table_Int (Namid);
+
+   begin
+      --  Return No_Uint if no information is available for the component
+
+      if Index = 0 then
+         return No_Uint;
+      end if;
+
+      return JSON_Component_Table.Table (Index).Bit_Offset;
+   end Get_JSON_Component_Bit_Offset;
+
+   -------------------------------
+   --  Get_JSON_Component_Size  --
+   -------------------------------
+
+   function Get_JSON_Component_Size (Name : String) return Node_Ref_Or_Val is
+      Namid : constant Valid_Name_Id := Name_Find (Name);
+      Index : constant Int := Get_Name_Table_Int (Namid);
+
+   begin
+      --  Return No_Uint if no information is available for the component
+
+      if Index = 0 then
+         return No_Uint;
+      end if;
+
+      return JSON_Entity_Table.Table (Index).Component_Size;
+   end Get_JSON_Component_Size;
+
+   ----------------------
+   --  Get_JSON_Esize  --
+   ----------------------
+
+   function Get_JSON_Esize (Name : String) return Node_Ref_Or_Val is
+      Namid : constant Valid_Name_Id := Name_Find (Name);
+      Index : constant Int := Get_Name_Table_Int (Namid);
+
+   begin
+      --  Return No_Uint if no information is available for the entity
+
+      if Index = 0 then
+         return No_Uint;
+      end if;
+
+      return JSON_Entity_Table.Table (Index).Esize;
+   end Get_JSON_Esize;
+
+   ----------------------
+   --  Get_JSON_Esize  --
+   ----------------------
+
+   function Get_JSON_Esize
+     (Name        : String;
+      Record_Name : String) return Node_Ref_Or_Val
+   is
+      Namid : constant Valid_Name_Id := Name_Find (Record_Name & '.' & Name);
+      Index : constant Int := Get_Name_Table_Int (Namid);
+
+   begin
+      --  Return No_Uint if no information is available for the entity
+
+      if Index = 0 then
+         return No_Uint;
+      end if;
+
+      return JSON_Component_Table.Table (Index).Esize;
+   end Get_JSON_Esize;
+
+   ------------------------
+   --  Get_JSON_RM_Size  --
+   ------------------------
+
+   function Get_JSON_RM_Size (Name : String) return Node_Ref_Or_Val is
+      Namid : constant Valid_Name_Id := Name_Find (Name);
+      Index : constant Int := Get_Name_Table_Int (Namid);
+
+   begin
+      --  Return No_Uint if no information is available for the entity
+
+      if Index = 0 then
+         return No_Uint;
+      end if;
+
+      return JSON_Entity_Table.Table (Index).RM_Size;
+   end Get_JSON_RM_Size;
+
+   -----------------------
+   --  Read_JSON_Stream --
+   -----------------------
+
+   procedure Read_JSON_Stream (Text : Text_Buffer; File_Name : String) is
+
+      type Text_Position is record
+         Index  : Text_Ptr := 0;
+         Line   : Natural := 0;
+         Column : Natural := 0;
+      end record;
+      --  Record to represent position in the text
+
+      type Token_Kind is
+        (J_NULL,
+         J_TRUE,
+         J_FALSE,
+         J_NUMBER,
+         J_INTEGER,
+         J_STRING,
+         J_ARRAY,
+         J_OBJECT,
+         J_ARRAY_END,
+         J_OBJECT_END,
+         J_COMMA,
+         J_COLON,
+         J_EOF);
+      --  JSON Token kind. Note that in ECMA 404 there is no notion of integer.
+      --  Only numbers are supported. In our implementation we return J_INTEGER
+      --  if there is no decimal part in the number. The semantic is that this
+      --  is a J_NUMBER token that might be represented as an integer. Special
+      --  token J_EOF means that end of stream has been reached.
+
+      function Decode_Integer (Lo, Hi : Text_Ptr) return Uint;
+      --  Decode and return the integer in Text (Lo .. Hi)
+
+      function Decode_Name (Lo, Hi : Text_Ptr) return Valid_Name_Id;
+      --  Decode and return the name in Text (Lo .. Hi)
+
+      function Decode_Symbol (Lo, Hi : Text_Ptr) return TCode;
+      --  Decode and return the expression symbol in Text (Lo .. Hi)
+
+      procedure Error (Msg : String);
+      pragma No_Return (Error);
+      --  Print an error message and raise an exception
+
+      procedure Read_Entity;
+      --  Read an entity
+
+      function Read_Name return Valid_Name_Id;
+      --  Read a name
+
+      function Read_Name_With_Prefix return Valid_Name_Id;
+      --  Read a name and prepend a prefix
+
+      function Read_Number return Uint;
+      --  Read a number
+
+      function Read_Numerical_Expr return Node_Ref_Or_Val;
+      --  Read a numerical expression
+
+      procedure Read_Record;
+      --  Read a record
+
+      function Read_String return Valid_Name_Id;
+      --  Read a string
+
+      procedure Read_Token
+        (Kind        : out Token_Kind;
+         Token_Start : out Text_Position;
+         Token_End   : out Text_Position);
+      --  Read a token and return it (this is a standard JSON lexer)
+
+      procedure Read_Token_And_Error
+        (TK          : Token_Kind;
+         Token_Start : out Text_Position;
+         Token_End   : out Text_Position);
+      pragma Inline (Read_Token_And_Error);
+      --  Read a specified token and error out on failure
+
+      function Read_Variant_Part return Nat;
+      --  Read a variant part
+
+      procedure Skip_Value;
+      --  Skip a value
+
+      Pos : Text_Position := (Text'First, 1, 1);
+      --  The current position in the text buffer
+
+      Name_Buffer : Bounded_String (4 * Max_Name_Length);
+      --  The buffer used to build full qualifed names
+
+      Prefix_Len : Natural := 0;
+      --  The length of the prefix present in Name_Buffer
+
+      ----------------------
+      --  Decode_Integer  --
+      ----------------------
+
+      function Decode_Integer (Lo, Hi : Text_Ptr) return Uint is
+         Len  : constant Nat := Int (Hi) - Int (Lo) + 1;
+
+      begin
+         --  Decode up to 9 characters manually, otherwise call into Uint
+
+         if Len < 10 then
+            declare
+               Val : Int := 0;
+
+            begin
+               for J in Lo .. Hi loop
+                  Val := Val * 10
+                           + Character'Pos (Text (J)) - Character'Pos ('0');
+               end loop;
+               return UI_From_Int (Val);
+            end;
+
+         else
+            declare
+               Val : Uint := Uint_0;
+
+            begin
+               for J in Lo .. Hi loop
+                  Val := Val * 10
+                           + Character'Pos (Text (J)) - Character'Pos ('0');
+               end loop;
+               return Val;
+            end;
+         end if;
+      end Decode_Integer;
+
+      -------------------
+      --  Decode_Name  --
+      -------------------
+
+      function Decode_Name (Lo, Hi : Text_Ptr) return Valid_Name_Id is
+      begin
+         --  Names are stored in lower case so fold them if need be
+
+         if Is_Upper_Case_Letter (Text (Lo)) then
+            declare
+               S : String (Integer (Lo) .. Integer (Hi));
+
+            begin
+               for J in Lo .. Hi loop
+                  S (Integer (J)) := Fold_Lower (Text (J));
+               end loop;
+
+               return Name_Find (S);
+            end;
+
+         else
+            declare
+               S : String (Integer (Lo) .. Integer (Hi));
+               for S'Address use Text (Lo)'Address;
+
+            begin
+               return Name_Find (S);
+            end;
+         end if;
+      end Decode_Name;
+
+      ---------------------
+      --  Decode_Symbol  --
+      ---------------------
+
+      function Decode_Symbol (Lo, Hi : Text_Ptr) return TCode is
+
+         function Cmp12 (A, B : Character) return Boolean;
+         pragma Inline (Cmp12);
+         --  Compare Text (Lo + 1 .. Lo + 2) with A & B.
+
+         -------------
+         --  Cmp12  --
+         -------------
+
+         function Cmp12 (A, B : Character) return Boolean is
+         begin
+            return Text (Lo + 1) = A and then Text (Lo + 2) = B;
+         end Cmp12;
+
+         Len : constant Nat := Int (Hi) - Int (Lo) + 1;
+
+      --  Start of processing for Decode_Symbol
+
+      begin
+         case Len is
+            when 1 =>
+               case Text (Lo) is
+                  when '+' =>
+                     return Plus_Expr;
+                  when '-' =>
+                     return Minus_Expr; -- or Negate_Expr
+                  when '*' =>
+                     return Mult_Expr;
+                  when '<' =>
+                     return Lt_Expr;
+                  when '>' =>
+                     return Gt_Expr;
+                  when '&' =>
+                     return Bit_And_Expr;
+                  when '#' =>
+                     return Discrim_Val;
+                  when others =>
+                     null;
+               end case;
+            when 2 =>
+               if Text (Lo) = '/' then
+                  case Text (Lo + 1) is
+                     when 't' =>
+                        return Trunc_Div_Expr;
+                     when 'c' =>
+                        return Ceil_Div_Expr;
+                     when 'f' =>
+                        return Floor_Div_Expr;
+                     when 'e' =>
+                        return Exact_Div_Expr;
+                     when others =>
+                        null;
+                  end case;
+               elsif Text (Lo + 1) = '=' then
+                  case Text (Lo) is
+                     when '<' =>
+                        return Le_Expr;
+                     when '>' =>
+                        return Ge_Expr;
+                     when '=' =>
+                        return Eq_Expr;
+                     when '!' =>
+                        return Ne_Expr;
+                     when others =>
+                        null;
+                  end case;
+               elsif Text (Lo) = 'o' and then Text (Lo + 1) = 'r' then
+                  return Truth_Or_Expr;
+               end if;
+            when 3 =>
+               case Text (Lo) is
+                  when '?' =>
+                     if Cmp12 ('<', '>') then
+                        return Cond_Expr;
+                     end if;
+                  when 'a' =>
+                     if Cmp12 ('b', 's') then
+                        return Abs_Expr;
+                     elsif Cmp12 ('n', 'd') then
+                        return Truth_And_Expr;
+                     end if;
+                  when 'm' =>
+                     if Cmp12 ('a', 'x') then
+                        return Max_Expr;
+                     elsif Cmp12 ('i', 'n') then
+                        return Min_Expr;
+                     end if;
+                  when 'n' =>
+                     if Cmp12 ('o', 't') then
+                        return Truth_Not_Expr;
+                     end if;
+                  when 'x' =>
+                     if Cmp12 ('o', 'r') then
+                        return Truth_Xor_Expr;
+                     end if;
+                  when 'v' =>
+                     if Cmp12 ('a', 'r') then
+                        return Dynamic_Val;
+                     end if;
+                  when others =>
+                     null;
+               end case;
+            when 4 =>
+               if Text (Lo) = 'm'
+                 and then Text (Lo + 1) = 'o'
+                 and then Text (Lo + 2) = 'd'
+               then
+                  case Text (Lo + 3) is
+                     when 't' =>
+                        return Trunc_Mod_Expr;
+                     when 'c' =>
+                        return Ceil_Mod_Expr;
+                     when 'f' =>
+                        return Floor_Mod_Expr;
+                     when others =>
+                        null;
+                  end case;
+               end if;
+
+               pragma Annotate
+                 (CodePeer, Intentional,
+                  "condition predetermined", "Error called as defensive code");
+
+            when others =>
+               null;
+         end case;
+
+         Error ("unknown symbol");
+      end Decode_Symbol;
+
+      -----------
+      -- Error --
+      -----------
+
+      procedure Error (Msg : String) is
+         L : constant String := Pos.Line'Img;
+         C : constant String := Pos.Column'Img;
+
+      begin
+         Set_Standard_Error;
+         Write_Eol;
+         Write_Str (File_Name);
+         Write_Char (':');
+         Write_Str (L (L'First + 1 .. L'Last));
+         Write_Char (':');
+         Write_Str (C (C'First + 1 .. C'Last));
+         Write_Char (':');
+         Write_Line (Msg);
+         raise Invalid_JSON_Stream;
+      end Error;
+
+      ------------------
+      --  Read_Entity --
+      ------------------
+
+      procedure Read_Entity is
+         Ent         : JSON_Entity_Node;
+         Nam         : Name_Id := No_Name;
+         Siz         : Node_Ref_Or_Val;
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+         TK          : Token_Kind;
+
+      begin
+         Ent.Esize          := No_Uint;
+         Ent.RM_Size        := No_Uint;
+         Ent.Component_Size := No_Uint;
+
+         --  Read the members as string : value pairs
+
+         loop
+            case Read_String is
+               when Name_Name =>
+                  Nam := Read_Name;
+               when Name_Record =>
+                  if Nam = No_Name then
+                     Error ("name expected");
+                  end if;
+                  Ent.Variant := 0;
+                  Prefix_Len := Natural (Length_Of_Name (Nam));
+                  Name_Buffer.Chars (1 .. Prefix_Len) := Get_Name_String (Nam);
+                  Read_Record;
+               when Name_Variant =>
+                  Ent.Variant := Read_Variant_Part;
+               when Name_Size =>
+                  Siz := Read_Numerical_Expr;
+                  Ent.Esize := Siz;
+                  Ent.RM_Size := Siz;
+               when Name_Object_Size =>
+                  Ent.Esize := Read_Numerical_Expr;
+               when Name_Value_Size =>
+                  Ent.RM_Size := Read_Numerical_Expr;
+               when Name_Component_Size =>
+                  Ent.Component_Size := Read_Numerical_Expr;
+               when others =>
+                  Skip_Value;
+            end case;
+
+            Read_Token (TK, Token_Start, Token_End);
+            if TK = J_OBJECT_END then
+               exit;
+            elsif TK /= J_COMMA then
+               Error ("comma expected");
+            end if;
+         end loop;
+
+         --  Store the entity into the table
+
+         JSON_Entity_Table.Append (Ent);
+
+         --  Associate the name with the entity
+
+         if Nam = No_Name then
+            Error ("name expected");
+         end if;
+
+         Set_Name_Table_Int (Nam, JSON_Entity_Table.Last);
+      end Read_Entity;
+
+      -----------------
+      --  Read_Name  --
+      -----------------
+
+      function Read_Name return Valid_Name_Id is
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+
+      begin
+         --  Read a single string
+
+         Read_Token_And_Error (J_STRING, Token_Start, Token_End);
+
+         return Decode_Name (Token_Start.Index + 1, Token_End.Index - 1);
+      end Read_Name;
+
+      -----------------------------
+      --  Read_Name_With_Prefix  --
+      -----------------------------
+
+      function Read_Name_With_Prefix return Valid_Name_Id is
+         Len         : Natural;
+         Lo, Hi      : Text_Ptr;
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+
+      begin
+         --  Read a single string
+
+         Read_Token_And_Error (J_STRING, Token_Start, Token_End);
+         Lo := Token_Start.Index + 1;
+         Hi := Token_End.Index - 1;
+
+         --  Prepare for the concatenation with the prefix
+
+         Len := Integer (Hi) - Integer (Lo) + 1;
+         if Prefix_Len + 1 + Len > Name_Buffer.Max_Length then
+            Error ("Name buffer too small");
+         end if;
+
+         Name_Buffer.Length := Prefix_Len + 1 + Len;
+         Name_Buffer.Chars (Prefix_Len + 1) := '.';
+
+         --  Names are stored in lower case so fold them if need be
+
+         if Is_Upper_Case_Letter (Text (Lo)) then
+            for J in Lo .. Hi loop
+               Name_Buffer.Chars (Prefix_Len + 2 + Integer (J - Lo)) :=
+                                                         Fold_Lower (Text (J));
+            end loop;
+
+         else
+            declare
+               S : String (Integer (Lo) .. Integer (Hi));
+               for S'Address use Text (Lo)'Address;
+
+            begin
+               Name_Buffer.Chars (Prefix_Len + 2 .. Prefix_Len + 1 + Len) := S;
+            end;
+         end if;
+
+         return Name_Find (Name_Buffer);
+      end Read_Name_With_Prefix;
+
+      ------------------
+      --  Read_Number --
+      ------------------
+
+      function Read_Number return Uint is
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+
+      begin
+         --  Only integers are to be expected here
+
+         Read_Token_And_Error (J_INTEGER, Token_Start, Token_End);
+
+         return Decode_Integer (Token_Start.Index, Token_End.Index);
+      end Read_Number;
+
+      --------------------------
+      --  Read_Numerical_Expr --
+      --------------------------
+
+      function Read_Numerical_Expr return Node_Ref_Or_Val is
+         Code        : TCode;
+         Nop         : Integer;
+         Ops         : array (1 .. 3) of Node_Ref_Or_Val;
+         TK          : Token_Kind;
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+
+      begin
+         --  Read either an integer or an expression
+
+         Read_Token (TK, Token_Start, Token_End);
+         if TK = J_INTEGER then
+            return Decode_Integer (Token_Start.Index, Token_End.Index);
+
+         elsif TK = J_OBJECT then
+            --  Read the code of the expression and decode it
+
+            if Read_String /= Name_Code then
+               Error ("name expected");
+            end if;
+
+            Read_Token_And_Error (J_STRING, Token_Start, Token_End);
+            Code := Decode_Symbol (Token_Start.Index + 1, Token_End.Index - 1);
+            Read_Token_And_Error (J_COMMA, Token_Start, Token_End);
+
+            --  Read the array of operands
+
+            if Read_String /= Name_Operands then
+               Error ("operands expected");
+            end if;
+
+            Read_Token_And_Error (J_ARRAY, Token_Start, Token_End);
+
+            Nop := 0;
+            Ops := (others => No_Uint);
+            loop
+               Nop := Nop + 1;
+               Ops (Nop) := Read_Numerical_Expr;
+               Read_Token (TK, Token_Start, Token_End);
+               if TK = J_ARRAY_END then
+                  exit;
+               elsif TK /= J_COMMA then
+                  Error ("comma expected");
+               end if;
+            end loop;
+
+            Read_Token_And_Error (J_OBJECT_END, Token_Start, Token_End);
+
+            --  Resolve the ambiguity for '-' now
+
+            if Code = Minus_Expr and then Nop = 1 then
+               Code := Negate_Expr;
+            end if;
+
+            return Create_Node (Code, Ops (1), Ops (2), Ops (3));
+
+         else
+            Error ("numerical expression expected");
+         end if;
+      end Read_Numerical_Expr;
+
+      -------------------
+      --  Read_Record  --
+      -------------------
+
+      procedure Read_Record is
+         Comp        : JSON_Component_Node;
+         First_Bit   : Node_Ref_Or_Val := No_Uint;
+         Is_First    : Boolean := True;
+         Nam         : Name_Id := No_Name;
+         Position    : Node_Ref_Or_Val := No_Uint;
+         TK          : Token_Kind;
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+
+      begin
+         --  Read a possibly empty array of components
+
+         Read_Token_And_Error (J_ARRAY, Token_Start, Token_End);
+
+         loop
+            Read_Token (TK, Token_Start, Token_End);
+            if Is_First and then TK = J_ARRAY_END then
+               exit;
+            elsif TK /= J_OBJECT then
+               Error ("object expected");
+            end if;
+
+            --  Read the members as string : value pairs
+
+            loop
+               case Read_String is
+                  when Name_Name =>
+                     Nam := Read_Name_With_Prefix;
+                  when Name_Discriminant =>
+                     Skip_Value;
+                  when Name_Position =>
+                     Position := Read_Numerical_Expr;
+                  when Name_First_Bit =>
+                     First_Bit := Read_Number;
+                  when Name_Size =>
+                     Comp.Esize := Read_Numerical_Expr;
+                  when others =>
+                     Error ("invalid component");
+               end case;
+
+               Read_Token (TK, Token_Start, Token_End);
+               if TK = J_OBJECT_END then
+                  exit;
+               elsif TK /= J_COMMA then
+                  Error ("comma expected");
+               end if;
+            end loop;
+
+            --  Compute Component_Bit_Offset from Position and First_Bit,
+            --  either symbolically or literally depending on Position.
+
+            if Position = No_Uint or else First_Bit = No_Uint then
+               Error ("bit offset expected");
+            end if;
+
+            if Position < Uint_0 then
+               declare
+                  Bit_Position : constant Node_Ref_Or_Val :=
+                          Create_Node (Mult_Expr, Position, UI_From_Int (SSU));
+               begin
+                  if First_Bit = Uint_0 then
+                     Comp.Bit_Offset := Bit_Position;
+                  else
+                     Comp.Bit_Offset :=
+                              Create_Node (Plus_Expr, Bit_Position, First_Bit);
+                  end if;
+               end;
+            else
+               Comp.Bit_Offset := Position * SSU + First_Bit;
+            end if;
+
+            --  Store the component into the table
+
+            JSON_Component_Table.Append (Comp);
+
+            --  Associate the name with the component
+
+            if Nam = No_Name then
+               Error ("name expected");
+            end if;
+
+            Set_Name_Table_Int (Nam, JSON_Component_Table.Last);
+
+            Read_Token (TK, Token_Start, Token_End);
+            if TK = J_ARRAY_END then
+               exit;
+            elsif TK /= J_COMMA then
+               Error ("comma expected");
+            end if;
+
+            Is_First := False;
+         end loop;
+      end Read_Record;
+
+      ------------------
+      --  Read_String --
+      ------------------
+
+      function Read_String return Valid_Name_Id is
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+         Nam         : Valid_Name_Id;
+
+      begin
+         --  Read the string and the following colon
+
+         Read_Token_And_Error (J_STRING, Token_Start, Token_End);
+         Nam := Decode_Name (Token_Start.Index + 1, Token_End.Index - 1);
+         Read_Token_And_Error (J_COLON, Token_Start, Token_End);
+
+         return Nam;
+      end Read_String;
+
+      ------------------
+      --  Read_Token  --
+      ------------------
+
+      procedure Read_Token
+        (Kind        : out Token_Kind;
+         Token_Start : out Text_Position;
+         Token_End   : out Text_Position)
+      is
+         procedure Next_Char;
+         --  Update Pos to point to next char
+
+         function Is_Whitespace return Boolean;
+         pragma Inline (Is_Whitespace);
+         --  Return True of current character is a whitespace
+
+         function Is_Structural_Token return Boolean;
+         pragma Inline (Is_Structural_Token);
+         --  Return True if current character is one of the structural tokens
+
+         function Is_Token_Sep return Boolean;
+         pragma Inline (Is_Token_Sep);
+         --  Return True if current character is a token separator
+
+         procedure Delimit_Keyword (Kw : String);
+         --  Helper function to parse tokens such as null, false and true
+
+         ---------------
+         -- Next_Char --
+         ---------------
+
+         procedure Next_Char is
+         begin
+            if Pos.Index > Text'Last then
+               Pos.Column := Pos.Column + 1;
+            elsif Text (Pos.Index) = ASCII.LF then
+               Pos.Column := 1;
+               Pos.Line := Pos.Line + 1;
+            else
+               Pos.Column := Pos.Column + 1;
+            end if;
+            Pos.Index := Pos.Index + 1;
+         end Next_Char;
+
+         -------------------
+         -- Is_Whitespace --
+         -------------------
+
+         function Is_Whitespace return Boolean is
+         begin
+            return
+              Pos.Index <= Text'Last
+                and then
+              (Text (Pos.Index) = ASCII.LF
+                 or else
+               Text (Pos.Index) = ASCII.CR
+                 or else
+               Text (Pos.Index) = ASCII.HT
+                 or else
+               Text (Pos.Index) = ' ');
+         end Is_Whitespace;
+
+         -------------------------
+         -- Is_Structural_Token --
+         -------------------------
+
+         function Is_Structural_Token return Boolean is
+         begin
+            return
+              Pos.Index <= Text'Last
+                and then
+              (Text (Pos.Index) = '['
+                 or else
+               Text (Pos.Index) = ']'
+                 or else
+               Text (Pos.Index) = '{'
+                 or else
+               Text (Pos.Index) = '}'
+                 or else
+               Text (Pos.Index) = ','
+                 or else
+               Text (Pos.Index) = ':');
+         end Is_Structural_Token;
+
+         ------------------
+         -- Is_Token_Sep --
+         ------------------
+
+         function Is_Token_Sep return Boolean is
+         begin
+            return
+              Pos.Index > Text'Last
+                or else
+              Is_Whitespace
+                or else
+              Is_Structural_Token;
+         end Is_Token_Sep;
+
+         ---------------------
+         -- Delimit_Keyword --
+         ---------------------
+
+         procedure Delimit_Keyword (Kw : String) is
+            pragma Unreferenced (Kw);
+         begin
+            while not Is_Token_Sep loop
+               Token_End := Pos;
+               Next_Char;
+            end loop;
+         end Delimit_Keyword;
+
+         CC             : Character;
+         Can_Be_Integer : Boolean := True;
+
+      --  Start of processing for Read_Token
+
+      begin
+         --  Skip leading whitespaces
+
+         while Is_Whitespace loop
+            Next_Char;
+         end loop;
+
+         --  Initialize token delimiters
+
+         Token_Start := Pos;
+         Token_End   := Pos;
+
+         --  End of stream reached
+
+         if Pos.Index > Text'Last then
+            Kind := J_EOF;
+            return;
+         end if;
+
+         CC := Text (Pos.Index);
+
+         if CC = '[' then
+            Next_Char;
+            Kind := J_ARRAY;
+            return;
+         elsif CC = ']' then
+            Next_Char;
+            Kind := J_ARRAY_END;
+            return;
+         elsif CC = '{' then
+            Next_Char;
+            Kind := J_OBJECT;
+            return;
+         elsif CC = '}' then
+            Next_Char;
+            Kind := J_OBJECT_END;
+            return;
+         elsif CC = ',' then
+            Next_Char;
+            Kind := J_COMMA;
+            return;
+         elsif CC = ':' then
+            Next_Char;
+            Kind := J_COLON;
+            return;
+         elsif CC = 'n' then
+            Delimit_Keyword ("null");
+            Kind := J_NULL;
+            return;
+         elsif CC = 'f' then
+            Delimit_Keyword ("false");
+            Kind := J_FALSE;
+            return;
+         elsif CC = 't' then
+            Delimit_Keyword ("true");
+            Kind := J_TRUE;
+            return;
+         elsif CC = '"' then
+            --  We expect a string
+            --  Just scan till the end the of the string but do not attempt
+            --  to decode it. This means that even if we get a string token
+            --  it might not be a valid string from the ECMA 404 point of
+            --  view.
+
+            Next_Char;
+            while Pos.Index <= Text'Last and then Text (Pos.Index) /= '"' loop
+               if Text (Pos.Index) in ASCII.NUL .. ASCII.US then
+                  Error ("control character not allowed in string");
+               end if;
+
+               if Text (Pos.Index) = '\' then
+                  Next_Char;
+                  if Pos.Index > Text'Last then
+                     Error ("non terminated string token");
+                  end if;
+
+                  case Text (Pos.Index) is
+                     when 'u' =>
+                        for Idx in 1 .. 4 loop
+                           Next_Char;
+                           if Pos.Index > Text'Last
+                             or else (Text (Pos.Index) not in 'a' .. 'f'
+                                        and then
+                                      Text (Pos.Index) not in 'A' .. 'F'
+                                        and then
+                                      Text (Pos.Index) not in '0' .. '9')
+                           then
+                              Error ("invalid unicode escape sequence");
+                           end if;
+                        end loop;
+                     when '\' | '/' | '"' | 'b' | 'f' | 'n' | 'r' | 't' =>
+                        null;
+                     when others =>
+                        Error ("invalid escape sequence");
+                  end case;
+               end if;
+               Next_Char;
+            end loop;
+
+            --  No quote found report and error
+
+            if Pos.Index > Text'Last then
+               Error ("non terminated string token");
+            end if;
+
+            Token_End := Pos;
+
+            --  Go to next char and ensure that this is separator. Indeed
+            --  construction such as "string1""string2" are not allowed
+
+            Next_Char;
+            if not Is_Token_Sep then
+               Error ("invalid syntax");
+            end if;
+            Kind := J_STRING;
+            return;
+         elsif CC = '-' or else CC in '0' .. '9' then
+            --  We expect a number
+            if CC = '-' then
+               Next_Char;
+            end if;
+
+            if Pos.Index > Text'Last then
+               Error ("invalid number");
+            end if;
+
+            --  Parse integer part of a number. Superfluous leading zeros are
+            --  not allowed.
+
+            if Text (Pos.Index) = '0' then
+               Token_End := Pos;
+               Next_Char;
+            elsif Text (Pos.Index) in '1' .. '9' then
+               Token_End := Pos;
+               Next_Char;
+               while Pos.Index <= Text'Last
+                 and then Text (Pos.Index) in '0' .. '9'
+               loop
+                  Token_End := Pos;
+                  Next_Char;
+               end loop;
+            else
+               Error ("invalid number");
+            end if;
+
+            if Is_Token_Sep then
+               --  Valid integer number
+
+               Kind := J_INTEGER;
+               return;
+            elsif Text (Pos.Index) /= '.'
+              and then Text (Pos.Index) /= 'e'
+              and then Text (Pos.Index) /= 'E'
+            then
+               Error ("invalid number");
+            end if;
+
+            --  Check for a fractional part
+
+            if Text (Pos.Index) = '.' then
+               Can_Be_Integer := False;
+               Token_End := Pos;
+               Next_Char;
+               if Pos.Index > Text'Last
+                 or else Text (Pos.Index) not in '0' .. '9'
+               then
+                  Error ("invalid number");
+               end if;
+
+               while Pos.Index <= Text'Last
+                 and then Text (Pos.Index) in '0' .. '9'
+               loop
+                  Token_End := Pos;
+                  Next_Char;
+               end loop;
+
+            end if;
+
+            --  Check for exponent part
+
+            if Pos.Index <= Text'Last
+              and then (Text (Pos.Index) = 'e' or else Text (Pos.Index) = 'E')
+            then
+               Token_End := Pos;
+               Next_Char;
+               if Pos.Index > Text'Last then
+                  Error ("invalid number");
+               end if;
+
+               if Text (Pos.Index) = '-' then
+                  --  Also a few corner cases can lead to an integer, assume
+                  --  that the number is not an integer.
+
+                  Can_Be_Integer := False;
+               end if;
+
+               if Text (Pos.Index) = '-' or else Text (Pos.Index) = '+' then
+                  Next_Char;
+               end if;
+
+               if Pos.Index > Text'Last
+                 or else Text (Pos.Index) not in '0' .. '9'
+               then
+                  Error ("invalid number");
+               end if;
+
+               while Pos.Index <= Text'Last
+                 and then Text (Pos.Index) in '0' .. '9'
+               loop
+                  Token_End := Pos;
+                  Next_Char;
+               end loop;
+            end if;
+
+            if Is_Token_Sep then
+               --  Valid decimal number
+
+               if Can_Be_Integer then
+                  Kind := J_INTEGER;
+               else
+                  Kind := J_NUMBER;
+               end if;
+               return;
+            else
+               Error ("invalid number");
+            end if;
+         elsif CC = EOF then
+            Kind := J_EOF;
+         else
+            Error ("Unexpected character");
+         end if;
+      end Read_Token;
+
+      ----------------------------
+      --  Read_Token_And_Error  --
+      ----------------------------
+
+      procedure Read_Token_And_Error
+        (TK          : Token_Kind;
+         Token_Start : out Text_Position;
+         Token_End   : out Text_Position)
+      is
+         Kind : Token_Kind;
+
+      begin
+         --  Read a token and errout out if not of the expected kind
+
+         Read_Token (Kind, Token_Start, Token_End);
+         if Kind /= TK then
+            Error ("specific token expected");
+         end if;
+      end Read_Token_And_Error;
+
+      -------------------------
+      --  Read_Variant_Part  --
+      -------------------------
+
+      function Read_Variant_Part return Nat is
+         Next        : Nat := 0;
+         TK          : Token_Kind;
+         Token_Start : Text_Position;
+         Token_End   : Text_Position;
+         Var         : JSON_Variant_Node;
+
+      begin
+         --  Read a non-empty array of components
+
+         Read_Token_And_Error (J_ARRAY, Token_Start, Token_End);
+
+         loop
+            Read_Token_And_Error (J_OBJECT, Token_Start, Token_End);
+
+            Var.Variant := 0;
+
+            --  Read the members as string : value pairs
+
+            loop
+               case Read_String is
+                  when Name_Present =>
+                     Var.Present := Read_Numerical_Expr;
+                  when Name_Record =>
+                     Read_Record;
+                  when Name_Variant =>
+                     Var.Variant := Read_Variant_Part;
+                  when others =>
+                     Error ("invalid variant");
+               end case;
+
+               Read_Token (TK, Token_Start, Token_End);
+               if TK = J_OBJECT_END then
+                  exit;
+               elsif TK /= J_COMMA then
+                  Error ("comma expected");
+               end if;
+            end loop;
+
+            --  Chain the variant and store it into the table
+
+            Var.Next := Next;
+            JSON_Variant_Table.Append (Var);
+            Next := JSON_Variant_Table.Last;
+
+            Read_Token (TK, Token_Start, Token_End);
+            if TK = J_ARRAY_END then
+               exit;
+            elsif TK /= J_COMMA then
+               Error ("comma expected");
+            end if;
+         end loop;
+
+         return Next;
+      end Read_Variant_Part;
+
+      ------------------
+      --  Skip_Value  --
+      ------------------
+
+      procedure Skip_Value is
+         Array_Depth  : Natural := 0;
+         Object_Depth : Natural := 0;
+         TK           : Token_Kind;
+         Token_Start  : Text_Position;
+         Token_End    : Text_Position;
+
+      begin
+         --  Read a value without recursing
+
+         loop
+            Read_Token (TK, Token_Start, Token_End);
+
+            case TK is
+               when J_STRING | J_INTEGER | J_NUMBER =>
+                  null;
+               when J_ARRAY =>
+                  Array_Depth := Array_Depth + 1;
+               when J_ARRAY_END =>
+                  Array_Depth := Array_Depth - 1;
+               when J_OBJECT =>
+                  Object_Depth := Object_Depth + 1;
+               when J_OBJECT_END =>
+                  Object_Depth := Object_Depth - 1;
+               when J_COLON | J_COMMA =>
+                  if Array_Depth = 0 and then Object_Depth = 0 then
+                     Error ("value expected");
+                  end if;
+               when others =>
+                  Error ("value expected");
+            end case;
+
+            exit when Array_Depth = 0 and then Object_Depth = 0;
+         end loop;
+      end Skip_Value;
+
+      Token_Start : Text_Position;
+      Token_End   : Text_Position;
+      TK          : Token_Kind;
+      Is_First    : Boolean := True;
+
+   --  Start of processing for Read_JSON_Stream
+
+   begin
+      --  Read a possibly empty array of entities
+
+      Read_Token_And_Error (J_ARRAY, Token_Start, Token_End);
+
+      loop
+         Read_Token (TK, Token_Start, Token_End);
+         if Is_First and then TK = J_ARRAY_END then
+            exit;
+         elsif TK /= J_OBJECT then
+            Error ("object expected");
+         end if;
+
+         Read_Entity;
+
+         Read_Token (TK, Token_Start, Token_End);
+         if TK = J_ARRAY_END then
+            exit;
+         elsif TK /= J_COMMA then
+            Error ("comma expected");
+         end if;
+
+         Is_First := False;
+      end loop;
+   end Read_JSON_Stream;
+
+end Repinfo.Input;
--- /dev/null
+++ b/src/gcc/ada/repinfo-input.ads
@@ -0,0 +1,78 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--                         R E P I N F O - I N P U T                        --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--          Copyright (C) 2018-2019, Free Software Foundation, Inc.         --
+--                                                                          --
+-- GNAT is free software;  you can  redistribute it  and/or modify it under --
+-- terms of the  GNU General Public License as published  by the Free Soft- --
+-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
+-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
+-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
+-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
+--                                                                          --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception,   --
+-- version 3.1, as published by the Free Software Foundation.               --
+--                                                                          --
+-- You should have received a copy of the GNU General Public License and    --
+-- a copy of the GCC Runtime Library Exception along with this program;     --
+-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
+-- <http://www.gnu.org/licenses/>.                                          --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This package provides an alternate way of populating the internal tables
+--  of Repinfo from a JSON input rather than the binary blob of the tree file.
+--  Note that this is an additive mechanism, i.e. nothing is destroyed in the
+--  internal state of the unit when it is used.
+
+--  The first step is to feed the unit with a JSON stream of a specified format
+--  (see the spec of Repinfo for its description) by means of Read_JSON_Stream.
+--  Then, for each entity whose representation information is present in the
+--  JSON stream, the appropriate Get_JSON_* routines can be invoked to override
+--  the eponymous fields of the entity in the tree.
+
+package Repinfo.Input is
+
+   function Get_JSON_Esize (Name : String) return Node_Ref_Or_Val;
+   --  Returns the Esize value of the entity specified by Name, which is not
+   --  the component of a record type, or else No_Uint if no representation
+   --  information was supplied for the entity. Name is the full qualified name
+   --  of the entity in lower case letters.
+
+   function Get_JSON_RM_Size (Name : String) return Node_Ref_Or_Val;
+   --  Likewise for the RM_Size
+
+   function Get_JSON_Component_Size (Name : String) return Node_Ref_Or_Val;
+   --  Likewise for the Component_Size of an array type
+
+   function Get_JSON_Component_Bit_Offset
+     (Name        : String;
+      Record_Name : String) return Node_Ref_Or_Val;
+   --  Returns the Component_Bit_Offset of the component specified by Name,
+   --  which is declared in the record type specified by Record_Name, or else
+   --  No_Uint if no representation information was supplied for the component.
+   --  Name is the unqualified name of the component whereas Record_Name is the
+   --  full qualified name of the record type, both in lower case letters.
+
+   function Get_JSON_Esize
+     (Name        : String;
+      Record_Name : String) return Node_Ref_Or_Val;
+   --  Likewise for the Esize
+
+   Invalid_JSON_Stream : exception;
+   --  Raised if a format error is detected in the JSON stream
+
+   procedure Read_JSON_Stream (Text : Text_Buffer; File_Name : String);
+   --  Reads a JSON stream and populates internal tables from it. File_Name is
+   --  only used in error messages issued by the JSON parser.
+
+end Repinfo.Input;
--- a/src/gcc/ada/snames.ads-tmpl
+++ b/src/gcc/ada/snames.ads-tmpl
@@ -1511,6 +1511,11 @@
    Name_Runtime_Library_Dir              : constant Name_Id := N + $;
    Name_Runtime_Source_Dir               : constant Name_Id := N + $;
 
+   --  Additional names used by the Repinfo unit
+
+   Name_Discriminant                     : constant Name_Id := N + $;
+   Name_Operands                         : constant Name_Id := N + $;
+
    --  Other miscellaneous names used in front end
 
    Name_Unaligned_Valid                  : constant Name_Id := N + $;