Improve error message for #560.

2 files changed, 19 insertions, 1 deletions

diff --git a/src/vhdl/sem_names.adb b/src/vhdl/sem_names.adb
index d8d7dea6e..141563292 100644
--- a/src/vhdl/sem_names.adb
+++ b/src/vhdl/sem_names.adb
@@ -1830,7 +1830,15 @@ package body Sem_Names is
       if not Valid_Interpretation (Interpretation) then
          --  Unknown name.
          if not Soft then
-            Error_Msg_Sem (+Name, "no declaration for %i", +Name);
+            Interpretation := Get_Interpretation_Raw (Id);
+            if Valid_Interpretation (Interpretation)
+              and then Is_Conflict_Declaration (Interpretation)
+            then
+               Error_Msg_Sem
+                 (+Name, "no declaration for %i (due to conflicts)", +Name);
+            else
+               Error_Msg_Sem (+Name, "no declaration for %i", +Name);
+            end if;
          end if;
          Res := Error_Mark;
       elsif not Valid_Interpretation (Get_Next_Interpretation (Interpretation))
diff --git a/src/vhdl/sem_scopes.ads b/src/vhdl/sem_scopes.ads
index 6942c5430..3503d4fb6 100644
--- a/src/vhdl/sem_scopes.ads
+++ b/src/vhdl/sem_scopes.ads
@@ -105,6 +105,16 @@ package Sem_Scopes is
      return Boolean;
    pragma Inline (Is_In_Current_Declarative_Region);
 
+   --  Return the raw interpretation of ID.  To be used only in case of
+   --  invalid interpretation to clarify the issue: this may be due to
+   --  conflicting declarations.
+   function Get_Interpretation_Raw (Id : Name_Id)
+                                   return Name_Interpretation_Type;
+
+   --  Return True iff NI is a conflicting declaration.
+   function Is_Conflict_Declaration (Ni : Name_Interpretation_Type)
+                                    return Boolean;
+
    -- Push and pop all interpretations.
    -- This can be used to suspend name interpretation, in case of recursive
    -- semantics.