ruby: fix use of NULL variable when displaying exception

ChangeLog.adoc

@@ -10,6 +10,13 @@ This document lists all the changes for each version. +
 For a list of important changes that require manual actions, please look at release notes.
 
 
+[[v4.1.2]]
+== Version 4.1.2 (under dev)
+
+Bug fixes::
+
+  * ruby: fix use of NULL variable when displaying exception
+
 [[v4.1.1]]
 == Version 4.1.1 (2023-10-26)
 

ReleaseNotes.adoc

@@ -11,6 +11,11 @@ It is recommended to read it when upgrading to a new stable version. +
 For a complete list of changes, please look at ChangeLog.
 
 
+[[v4.1.2]]
+== Version 4.1.2 (under dev)
+
+No release notes.
+
 [[v4.1.1]]
 == Version 4.1.1 (2023-10-26)
 

src/plugins/ruby/weechat-ruby.c

@@ -287,7 +287,7 @@ weechat_ruby_print_exception (VALUE err)
         err_class = StringValuePtr (class_name);
     }
 
-    if (strcmp (err_class, "SyntaxError") == 0)
+    if (err_class && (strcmp (err_class, "SyntaxError") == 0))
     {
         tmp3 = rb_inspect (err);
         weechat_printf (NULL,