From: Matthew Fernandez <matthew.fernandez@gmail.com>
Date: Sat, 26 Mar 2022 00:30:58 +0000 (-0700)
Subject: lib/glcomp: fix -Wnon-literal-null-conversion with Clang
X-Git-Tag: 4.0.0~156^2~6
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=30dd7eb86f4e31bfa26abda9bff763fe01893f29;p=graphviz

lib/glcomp: fix -Wnon-literal-null-conversion with Clang

This was causing the CMake build (to be enabled in a future commit) on macOS to
fail.

Gitlab: #1836, #1854
---

diff --git a/lib/glcomp/glcompbutton.c b/lib/glcomp/glcompbutton.c
index 33290c1c9..97de80a3c 100644
--- a/lib/glcomp/glcompbutton.c
+++ b/lib/glcomp/glcompbutton.c
@@ -15,6 +15,7 @@
 #include <glcomp/glutils.h>
 #include <glcomp/glcompset.h>
 #include <common/memory.h>
+#include <stddef.h>
 #include <string.h>
 #include <GL/glut.h>
 
@@ -40,7 +41,7 @@ glCompButton *glCompButtonNew(glCompObj * par, GLfloat x, GLfloat y,
     p->common.height = h;
     p->status = 0;		//0 not pressed 1 pressed;
     p->groupid = 0;
-    p->common.callbacks.click = '\0';
+    p->common.callbacks.click = NULL;
     /*set event functions */
 
     p->common.functions.draw = (glcompdrawfunc_t)glCompButtonDraw;