From 52925ce9ff499a6cc180b9079a8ed44fb1c6b12c Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen <lars@metafoo.de>
Date: Thu, 6 Jan 2022 11:34:20 +0100
Subject: [PATCH] Handle invalid packed dimensions

Trying to elaborate a type with invalid packed dimensions currently results
in a crash. E.g. `typedef logic [] T;`

The issue is in the `elaborate_array_ranges()` function which
does not verify that the range specification is valid.

Replace the `elaborate_array_ranges()` with `evaluate_ranges()`, which does
the same thing, but properly checks the range specification and
reports an error if it is invalid.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 elab_type.cc | 44 ++++----------------------------------------
 1 file changed, 4 insertions(+), 40 deletions(-)

diff --git a/elab_type.cc b/elab_type.cc
index 49d3483df..4641b1507 100644
--- a/elab_type.cc
+++ b/elab_type.cc
@@ -34,44 +34,6 @@
 
 using namespace std;
 
-/*
- * Some types have a list of ranges that need to be elaborated. This
- * function elaborates the ranges referenced by "dims" into the vector
- * "ranges".
- */
-static void elaborate_array_ranges(Design*des, NetScope*scope,
-				   vector<netrange_t>&ranges,
-				   const list<pform_range_t>*dims)
-{
-      if (dims == 0)
-	    return;
-
-      for (list<pform_range_t>::const_iterator cur = dims->begin()
-		 ; cur != dims->end() ; ++ cur) {
-
-	    NetExpr*me = elab_and_eval(des, scope, cur->first, 0, true);
-
-	    NetExpr*le = elab_and_eval(des, scope, cur->second, 0, true);
-
-	      /* If elaboration failed for either expression, we
-		 should have already reported the error, so just
-		 skip the following evaluation to recover. */
-
-	    long mnum = 0, lnum = 0;
-	    if ( me && ! eval_as_long(mnum, me) ) {
-		  assert(0);
-		  des->errors += 1;
-	    }
-
-	    if ( le && ! eval_as_long(lnum, le) ) {
-		  assert(0);
-		  des->errors += 1;
-	    }
-
-	    ranges.push_back(netrange_t(mnum, lnum));
-      }
-}
-
 /*
  * Elaborations of types may vary depending on the scope that it is
  * done in, so keep a per-scope cache of the results.
@@ -164,7 +126,8 @@ ivl_type_s* enum_type_t::elaborate_type_raw(Design*, NetScope*scope) const
 ivl_type_s* vector_type_t::elaborate_type_raw(Design*des, NetScope*scope) const
 {
       vector<netrange_t> packed;
-      elaborate_array_ranges(des, scope, packed, pdims.get());
+      if (pdims.get())
+	    evaluate_ranges(des, scope, this, packed, *pdims);
 
       netvector_t*tmp = new netvector_t(packed, base_type);
       tmp->set_signed(signed_flag);
@@ -192,7 +155,8 @@ ivl_type_s* string_type_t::elaborate_type_raw(Design*, NetScope*) const
 ivl_type_s* parray_type_t::elaborate_type_raw(Design*des, NetScope*scope) const
 {
       vector<netrange_t>packed;
-      elaborate_array_ranges(des, scope, packed, dims.get());
+      if (dims.get())
+	    evaluate_ranges(des, scope, this, packed, *dims);
 
       ivl_type_t etype = base_type->elaborate_type(des, scope);