synth: improve handling of null-range nets.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/synth/synth-objtypes.ads b/src/synth/synth-objtypes.ads
index dfc0f732b..ff456d35f 100644
--- a/src/synth/synth-objtypes.ads
+++ b/src/synth/synth-objtypes.ads
@@ -125,6 +125,10 @@ package Synth.Objtypes is
       Sz : Size_Type;
 
       --  Number of bits (when in a net) for this type.
+      --  Can be zero only if the type has only 0 or 1 value (like a discrete
+      --  type with 1 element, a null vector, or a null array).
+      --  For non synthesizable types (like files or protected type), just
+      --  use 32.
       W : Width;
 
       case Kind is
@@ -292,6 +296,10 @@ package Synth.Objtypes is
    function Alloc_Memory (Vtype : Type_Acc) return Memory_Ptr;
    function Create_Memory (Vtype : Type_Acc) return Memtyp;
 
+   --  Like Create_Memory but initialize to 0.  To be used only for types
+   --  of width 0.
+   function Create_Memory_Zero (Vtype : Type_Acc) return Memtyp;
+
    function Is_Equal (L, R : Memtyp) return Boolean;
 
    procedure Copy_Memory (Dest : Memory_Ptr; Src : Memory_Ptr; Sz : Size_Type);