Bug#957914: Patch to fix linking with gcc-10

[arnold metselaar]

Dear maintainer,

Below and attached is a patch to make viking compile and link properly with
gcc-10.

Suggested changelog entry:

src/babel.h (a_babel_file_list, a_babel_device_list): declare global
variables as extern, closes #957914

Kind regards,
Arnold Metselaar
---

diff --git a/src/babel.h b/src/babel.h
index ae2fa959..e2c18e6c 100644
--- a/src/babel.h
+++ b/src/babel.h
@@ -109,8 +109,8 @@ typedef struct {
     gchar *label;
 } BabelFile;

-GList *a_babel_file_list;
-GList *a_babel_device_list;
+extern GList *a_babel_file_list;
+extern GList *a_babel_device_list;

 void a_babel_foreach_file_with_mode (BabelMode mode, GFunc func, gpointer
user_data);
 void a_babel_foreach_file_read_any (GFunc func, gpointer user_data);

diff --git a/src/babel.h b/src/babel.h
index ae2fa959..e2c18e6c 100644
--- a/src/babel.h
+++ b/src/babel.h
@@ -109,8 +109,8 @@ typedef struct {
     gchar *label;
 } BabelFile;
 
-GList *a_babel_file_list;
-GList *a_babel_device_list;
+extern GList *a_babel_file_list;
+extern GList *a_babel_device_list;
 
 void a_babel_foreach_file_with_mode (BabelMode mode, GFunc func, gpointer user_data);
 void a_babel_foreach_file_read_any (GFunc func, gpointer user_data);