From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Tue, 12 Dec 2023 23:47:46 +0000 (-0700)
Subject: Further guard against unnecessary copies.
X-Git-Tag: relicensing~250^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2a72b9a0a51d3a341f4e300c1f8fb2d1bc303811;p=dealii.git

Further guard against unnecessary copies.
---

diff --git a/source/grid/grid_generator.cc b/source/grid/grid_generator.cc
index 5ab4247afd..29656d165f 100644
--- a/source/grid/grid_generator.cc
+++ b/source/grid/grid_generator.cc
@@ -6596,13 +6596,13 @@ namespace GridGenerator
     // if either Triangulation is empty then merging is just a copy.
     if (triangulation_1.n_cells() == 0)
       {
-        result.copy_triangulation(triangulation_2);
-        return;
+        if (&result != &triangulation_2)
+          result.copy_triangulation(triangulation_2);
       }
     else if (triangulation_2.n_cells() == 0)
       {
-        result.copy_triangulation(triangulation_1);
-        return;
+        if (&result != &triangulation_1)
+          result.copy_triangulation(triangulation_1);
       }
     else
       merge_triangulations({&triangulation_1, &triangulation_2},