errorout: add nowrite warning. Fix #2081

During synthesis, emit a specific warning if a net is not assigned

5 files changed, 16 insertions, 8 deletions

diff --git a/src/errorout.ads b/src/errorout.ads
index 8cda8e69d..16515d8af 100644
--- a/src/errorout.ads
+++ b/src/errorout.ads
@@ -106,6 +106,10 @@ package Errorout is
       --  FIXME: currently only subprograms are handled.
       Warnid_Unused,
 
+      --  A variable or signal is never written.
+      --  (only for synthesis)
+      Warnid_Nowrite,
+
       --  Others choice is not needed, all values are already covered.
       Warnid_Others,
 
@@ -320,6 +324,7 @@ private
         | Warnid_Runtime_Error | Warnid_Pure | Warnid_Specs | Warnid_Hide
         | Warnid_Pragma | Warnid_Analyze_Assert | Warnid_Attribute
         | Warnid_Deprecated_Option | Warnid_Unexpected_Option
+        | Warnid_Nowrite
         | Warnid_No_Wait | Warnid_Useless
         | Msgid_Warning  => (Enabled => True, Error => False),
       Warnid_Delta_Cycle | Warnid_Body | Warnid_Static | Warnid_Nested_Comment
diff --git a/src/synth/synth-errors.adb b/src/synth/synth-errors.adb
index e8d693d0b..a0b672770 100644
--- a/src/synth/synth-errors.adb
+++ b/src/synth/synth-errors.adb
@@ -33,12 +33,12 @@ package body Synth.Errors is
                   +Loc, Msg, Args);
    end Error_Msg_Synth;
 
-   procedure Warning_Msg_Synth (Loc : Location_Type;
+   procedure Warning_Msg_Synth (Warnid : Msgid_Warnings;
+                                Loc : Location_Type;
                                 Msg : String;
                                 Arg1 : Earg_Type) is
    begin
-      Report_Msg (Msgid_Warning, Errorout.Elaboration,
-                  +Loc, Msg, (1 => Arg1));
+      Report_Msg (Warnid, Errorout.Elaboration, +Loc, Msg, (1 => Arg1));
    end Warning_Msg_Synth;
 
    procedure Warning_Msg_Synth (Loc : Location_Type;
diff --git a/src/synth/synth-errors.ads b/src/synth/synth-errors.ads
index 800f3232e..448ab6be1 100644
--- a/src/synth/synth-errors.ads
+++ b/src/synth/synth-errors.ads
@@ -26,7 +26,8 @@ package Synth.Errors is
    procedure Error_Msg_Synth (Loc : Location_Type;
                               Msg : String;
                               Args : Earg_Arr := No_Eargs);
-   procedure Warning_Msg_Synth (Loc : Location_Type;
+   procedure Warning_Msg_Synth (Warnid : Msgid_Warnings;
+                                Loc : Location_Type;
                                 Msg : String;
                                 Arg1 : Earg_Type);
    procedure Warning_Msg_Synth (Loc : Location_Type;
diff --git a/src/synth/synth-vhdl_decls.adb b/src/synth/synth-vhdl_decls.adb
index 96339dfcd..b6b00270e 100644
--- a/src/synth/synth-vhdl_decls.adb
+++ b/src/synth/synth-vhdl_decls.adb
@@ -18,6 +18,7 @@
 
 with Types; use Types;
 with Std_Names;
+with Errorout; use Errorout;
 
 with Netlists.Builders; use Netlists.Builders;
 with Netlists.Folds; use Netlists.Folds;
@@ -697,10 +698,11 @@ package body Synth.Vhdl_Decls is
             --  TODO: maybe simply remove it.
             if Def_Val = No_Net then
                Warning_Msg_Synth
-                 (+Decl, "%n is never assigned and has no default value",
-                  (1 => +Decl));
+                 (Warnid_Nowrite, +Decl,
+                  "%n is never assigned and has no default value", +Decl);
             else
-               Warning_Msg_Synth (+Decl, "%n is never assigned", (1 => +Decl));
+               Warning_Msg_Synth
+                 (Warnid_Nowrite, +Decl, "%n is never assigned", +Decl);
             end if;
          end if;
          if Def_Val = No_Net then
diff --git a/src/synth/synth-vhdl_environment.adb b/src/synth/synth-vhdl_environment.adb
index e86cd7a7c..7e726993c 100644
--- a/src/synth/synth-vhdl_environment.adb
+++ b/src/synth/synth-vhdl_environment.adb
@@ -50,7 +50,7 @@ package body Synth.Vhdl_Environment is
    begin
       if Last_Off < First_Off then
          Warning_Msg_Synth
-           (+Decl.Obj, "no assignment for %n", +Decl.Obj);
+           (Warnid_Nowrite, +Decl.Obj, "no assignment for %n", +Decl.Obj);
       elsif Last_Off = First_Off then
          Warning_Msg_Synth (+Decl.Obj, "no assignment for offset %v of %n",
                             (1 => +First_Off, 2 => +Decl.Obj));