guile: fix crash on quit with Guile < 3 (issue #1965)

ChangeLog.adoc

@@ -25,6 +25,7 @@ Bug fixes::
   * core: display actual key name and command with key kbd:[Alt+k], remove key kbd:[Alt+K] (grab raw key) and associated commands `/input grab_raw_key` and `/input grab_raw_key_command`
   * core: check for newline characters in string_is_whitespace_char (issue #1968)
   * api: do not convert option name to lower case in API functions config_set_plugin and config_set_desc_plugin
+  * guile: fix crash on quit with Guile < 3 (issue #1965)
   * irc: reply to a CTCP request sent to self nick (issue #1966)
   * irc: sent "QUIT" message to servers connected with TLS on `/upgrade`
   * irc: fix display of country code in message 344 received as whois geo info (issue #1736)

src/plugins/guile/weechat-guile.c

@@ -1289,7 +1289,16 @@ weechat_plugin_init (struct t_weechat_plugin *plugin, int argc, char *argv[])
     scm_install_gmp_memory_functions = 0;
 #endif /* defined(HAVE_GUILE_GMP_MEMORY_FUNCTIONS) && (SCM_MAJOR_VERSION < 3 || (SCM_MAJOR_VERSION == 3 && SCM_MINOR_VERSION == 0 && SCM_MICRO_VERSION < 8)) */
 
+#if defined(__MACH__) || SCM_MAJOR_VERSION < 3
+    /*
+     * on GNU/Hurd or if using Guile < 3, use scm_with_guile() instead of
+     * scm_init_guile() to prevent crash on exit
+     */
     scm_with_guile (&weechat_guile_init, NULL);
+#else
+    /* any other OS (not GNU/Hurd) or Guile >= 3.x */
+    scm_init_guile ();
+#endif
 
     guile_module_weechat = scm_c_define_module ("weechat",
                                                 &weechat_guile_api_module_init,