Add-on making re-registration of PCells a valid feature.

src/db/db/dbLayout.cc

@@ -2526,11 +2526,26 @@ Layout::register_pcell (const std::string &name, pcell_declaration_type *declara
     //  replace any existing PCell declaration with that name.
     id = pcid->second;
     if (m_pcells [id]) {
-      delete m_pcells [id];
+
+      std::unique_ptr<pcell_header_type> org_header (m_pcells [id]);
+      std::vector<pcell_variant_type *> variants;
+      for (auto v = org_header->begin (); v != org_header->end (); ++v) {
+        variants.push_back (v->second);
+      }
+      for (auto v = variants.begin (); v != variants.end (); ++v) {
+        (*v)->unregister ();
       }
 
       m_pcells [id] = new pcell_header_type (id, name, declaration);
 
+      for (auto v = variants.begin (); v != variants.end (); ++v) {
+        (*v)->reregister ();
+      }
+
+    } else {
+      m_pcells [id] = new pcell_header_type (id, name, declaration);
+    }
+
   } else {
 
     id = (unsigned int) m_pcells.size ();

testdata/ruby/dbPCells.rb

@@ -774,6 +774,41 @@ class DBPCell_TestClass < TestBase
 
   end
 
+  def test_11
+
+    lib = CircleLib1782::new("CircleLib")
+
+    ly = RBA::Layout::new
+
+    top = ly.create_cell("TOP")
+
+    names = []
+
+    c = ly.create_cell("Circle", "CircleLib", { "l" => RBA::LayerInfo::new(1, 0), "r" => 2.0, "n" => 64 })
+
+    # triggered another flavor of #1782
+    lib.reregister_pcell
+
+    c = ly.create_cell("Circle", "CircleLib", { "l" => RBA::LayerInfo::new(1, 0), "r" => 2.0, "n" => 64 })
+    top.insert(RBA::DCellInstArray::new(c, RBA::DTrans::new()))
+
+    tmp = File::join($ut_testtmp, "tmp.gds")
+    ly.write(tmp)
+
+    # this should not throw an internal error
+    ly._destroy
+
+    # we should be able to read the Layout back
+    ly = RBA::Layout::new
+    ly.read(tmp)
+    assert_equal(ly.top_cell.name, "TOP")
+    assert_equal(ly.cells, 2)
+    ly._destroy
+
+    lib._destroy
+
+  end
+
 end
 
 load("test_epilogue.rb")