Fix crash of implicit conversion in instantiation.

Fix #301

4 files changed, 24 insertions, 2 deletions

diff --git a/src/vhdl/translate/trans-chap5.adb b/src/vhdl/translate/trans-chap5.adb
index f4efc4103..dbccd5ac4 100644
--- a/src/vhdl/translate/trans-chap5.adb
+++ b/src/vhdl/translate/trans-chap5.adb
@@ -36,12 +36,23 @@ package body Trans.Chap5 is
               Scope => Scope_Ptr.all);
    end Save_Map_Env;
 
-   procedure Set_Map_Env (Env : Map_Env)
+   procedure Restore_Map_Env (Env : Map_Env)
    is
       --  Avoid potential compiler bug with discriminant check.
       pragma Suppress (Discriminant_Check);
    begin
       Env.Scope_Ptr.all := Env.Scope;
+   end Restore_Map_Env;
+
+   procedure Set_Map_Env (Env : Map_Env) is
+   begin
+      --  In some cases, the previous environment is still needed (for example
+      --  an implicit array conversion accesses to both the formal and the
+      --  actual type).  Set ENV only if it is not null, in order not to erase
+      --  the previous env.
+      if not Is_Null (Env.Scope) then
+         Restore_Map_Env (Env);
+      end if;
    end Set_Map_Env;
 
    procedure Translate_Attribute_Specification
@@ -742,7 +753,7 @@ package body Trans.Chap5 is
          end;
          Next_Association_Interface (Assoc, Inter);
       end loop;
-      Set_Map_Env (Actual_Env);
+      Restore_Map_Env (Actual_Env);
    end Elab_Port_Map_Aspect;
 
    procedure Elab_Generic_Map_Aspect
@@ -855,6 +866,7 @@ package body Trans.Chap5 is
          Close_Temp;
          Next_Association_Interface (Assoc, Inter);
       end loop;
+      Restore_Map_Env (Actual_Env);
    end Elab_Generic_Map_Aspect;
 
    procedure Elab_Map_Aspect
diff --git a/src/vhdl/translate/trans.adb b/src/vhdl/translate/trans.adb
index 1f9d177a4..6c8bc048e 100644
--- a/src/vhdl/translate/trans.adb
+++ b/src/vhdl/translate/trans.adb
@@ -432,6 +432,11 @@ package body Trans is
          Scope := (Scope_Type => Scope.Scope_Type, Kind => Var_Scope_None);
       end Clear_Scope;
 
+      function Is_Null (Scope : Var_Scope_Type) return Boolean is
+      begin
+         return Scope.Kind = Var_Scope_None;
+      end Is_Null;
+
       function Create_Global_Var
         (Name : O_Ident; Vtype : O_Tnode; Storage : O_Storage)
          return Var_Type
diff --git a/src/vhdl/translate/trans.ads b/src/vhdl/translate/trans.ads
index adc4a4712..cc74d46b5 100644
--- a/src/vhdl/translate/trans.ads
+++ b/src/vhdl/translate/trans.ads
@@ -324,6 +324,9 @@ package Trans is
       --  before being set.
       procedure Clear_Scope (Scope : in out Var_Scope_Type);
 
+      --  True if SCOPE is a null-scope (eg. was cleared).
+      function Is_Null (Scope : Var_Scope_Type) return Boolean;
+
       --  Reset the identifier.
       type Id_Mark_Type is limited private;
       type Local_Identifier_Type is private;
diff --git a/testsuite/gna/issue283/testsuite.sh b/testsuite/gna/issue283/testsuite.sh
index 13cf1d89c..4000acc12 100755
--- a/testsuite/gna/issue283/testsuite.sh
+++ b/testsuite/gna/issue283/testsuite.sh
@@ -1,5 +1,7 @@
 #! /bin/sh
 
 # Need cocotb
+# Was run with:
+# make COCOTB=/path/to/cocotb/ SIM=ghdl ARCH=x86_64 PYTHON_BIN=python TOPLEVEL_LANG=vhdl CMD=$GHDL
 
 echo "Test skipped"