1 files changed, 4 insertions, 0 deletions
diff --git a/src/xml/simple-node.cpp b/src/xml/simple-node.cpp
index 47f66ff85..fc74cfaec 100644
--- a/src/xml/simple-node.cpp
+++ b/src/xml/simple-node.cpp
@@ -13,6 +13,7 @@
  * Released under GNU GPL v2+, read the file 'COPYING' for more information.
  */
 
+#include <algorithm>
 #include <cstring>
 #include <string>
 
@@ -321,6 +322,9 @@ SimpleNode::setAttribute(gchar const *name, gchar const *value, bool const /*is_
 {
     g_return_if_fail(name && *name);
 
+    // sanity check: `name` must not contain whitespace
+    g_assert(std::none_of(name, name + strlen(name), [](char c) { return g_ascii_isspace(c); }));
+
     // Check usefulness of attributes on elements in the svg namespace, optionally don't add them to tree.
     Glib::ustring element = g_quark_to_string(_name);
     //g_message("setAttribute:  %s: %s: %s", element.c_str(), name, value);