Comment 7 for bug 1923642

No clang, that's with gcc 9.3.0.
I tried turning off aqbanking, ofx, dbi but that didn't help.
I'm not sure what the difference is, sorry.

I played around a bit and found a diff that made it compile on my system:

--- gnucash/gnome/assistant-loan.cpp.orig 2021-03-26 23:08:11.000000000 +0000
+++ gnucash/gnome/assistant-loan.cpp
@@ -23,6 +23,10 @@
  * Boston, MA 02110-1301, USA <email address hidden> *
 \********************************************************************/

+#include <glib.h>
+#include <glib/gi18n.h>
+#include <gtk/gtk.h>
+
 extern "C"
 {
 #include <config.h>
@@ -50,9 +54,6 @@ extern "C"
 #endif
 }

-#include <glib.h>
-#include <glib/gi18n.h>
-#include <gtk/gtk.h>
 #include <gnc-locale-utils.hpp>
 #include <boost/locale.hpp>
 #include <string>

I guess glib's multiple-inclusion-protection in the header saves us here :)