diff --git a/dev-tcltk/tkzinc/files/tkzinc-3.3.6-clang.patch b/dev-tcltk/tkzinc/files/tkzinc-3.3.6-clang.patch
new file mode 100644
index 0000000000000..e8bdb40b60830
--- /dev/null
+++ b/dev-tcltk/tkzinc/files/tkzinc-3.3.6-clang.patch
@@ -0,0 +1,29 @@
+--- a/generic/Window.c	2023-01-17 19:39:55.697886490 +0100
++++ b/generic/Window.c	2023-01-17 19:41:15.619618094 +0100
+@@ -350,7 +350,7 @@
+ #endif /* ifdef _WIN32 */
+ 
+    /* Reset externalwindow */
+-   wind->externalwindow = NULL;
++   wind->externalwindow = 0;
+ }
+ 
+ 
+@@ -384,7 +384,7 @@
+   wind->connection_anchor = TK_ANCHOR_SW;
+   wind->win = NULL;
+   wind->windowtitle = NULL;
+-  wind->externalwindow = NULL;
++  wind->externalwindow = 0;
+   
+   return TCL_OK;
+ }
+@@ -407,7 +407,7 @@
+    */
+   wind->win = NULL;
+   wind->windowtitle = NULL;
+-  wind->externalwindow = NULL;
++  wind->externalwindow = 0;
+ }
+ 
+ 
diff --git a/dev-tcltk/tkzinc/tkzinc-3.3.6-r1.ebuild b/dev-tcltk/tkzinc/tkzinc-3.3.6-r1.ebuild
index a94dde7d11fea..c7fa5fd154ebf 100644
--- a/dev-tcltk/tkzinc/tkzinc-3.3.6-r1.ebuild
+++ b/dev-tcltk/tkzinc/tkzinc-3.3.6-r1.ebuild
@@ -1,4 +1,4 @@
-# Copyright 1999-2021 Gentoo Authors
+# Copyright 1999-2023 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=8
@@ -26,7 +26,8 @@ S="${WORKDIR}/Tkzinc-${PV//.}+"
 PATCHES=(
 	"${FILESDIR}"/${PV}-ldflags.patch
 	"${FILESDIR}"/${PN}-3.3.4-latex.patch
-	)
+	"${FILESDIR}"/${P}-clang.patch
+)
 
 HTML_DOCS='doc/*png doc/*html doc/*css'