vhdl: avoid a crash on invalid actual conversion in association.

Fix #691

2 files changed, 7 insertions, 2 deletions

diff --git a/src/vhdl/sem_assocs.adb b/src/vhdl/sem_assocs.adb
index 971962288..299242a2f 100644
--- a/src/vhdl/sem_assocs.adb
+++ b/src/vhdl/sem_assocs.adb
@@ -1828,6 +1828,11 @@ package body Sem_Assocs is
                   null;
             end case;
 
+            if Actual = Null_Iir then
+               Match := Fully_Compatible;
+               return;
+            end if;
+
             --  There could be an ambiguity between a conversion and a normal
             --  actual expression.  Check if the new actual is an object and
             --  if the object is of the corresponding class.
diff --git a/src/vhdl/sem_names.adb b/src/vhdl/sem_names.adb
index b6150b8bb..033762bd5 100644
--- a/src/vhdl/sem_names.adb
+++ b/src/vhdl/sem_names.adb
@@ -2587,8 +2587,8 @@ package body Sem_Names is
       Assoc_Chain := Get_Association_Chain (Name);
       Actual := Get_One_Actual (Assoc_Chain);
 
-      if Kind_In (Prefix, Iir_Kind_Type_Declaration,
-                  Iir_Kind_Subtype_Declaration)
+      if Kind_In (Prefix,
+                  Iir_Kind_Type_Declaration, Iir_Kind_Subtype_Declaration)
       then
          --  A type conversion.  The prefix is a type mark.
          declare