maps-osm: Fix g_str_equal warnings from GLib >= 2.74

GLib 2.74 introduced an optimization for string comparison[1], but
that generates warnings similar to the following:

In file included from /usr/include/glib-2.0/glib.h:52,
                 from ../lib/maps-osm.h:23,
                 from ../lib/maps-osm.c:20:
../lib/maps-osm.c: In function 'parse_tag':
../lib/maps-osm.c:75:32: warning: pointer targets in passing argument 1 of 'strcmp' differ in signedness [-Wpointer-sign]
   75 |       if (g_str_equal (cur_attr->name, "k"))
/usr/include/glib-2.0/glib/ghash.h:165:39: note: in definition of macro 'g_str_equal'
  165 | #define g_str_equal(v1, v2) (strcmp ((v1), (v2)) == 0)
      |                                       ^~
In file included from /usr/include/fortify/string.h:22,
                 from /usr/include/glib-2.0/glib/galloca.h:35,
                 from /usr/include/glib-2.0/glib.h:32:
/usr/include/string.h:39:13: note: expected 'const char *' but argument is of type 'const xmlChar *' {aka 'const unsigned char *'}
   39 | int strcmp (const char *, const char *);
      |             ^~~~~~~~~~~~

Silence the warnings by casting the pointers to the correct type

[1] https://gitlab.gnome.org/GNOME/glib/-/merge_requests/2940

1 files changed, 10 insertions, 10 deletions

diff --git a/lib/maps-osm.c b/lib/maps-osm.c
index da03ffed..910c8782 100644
--- a/lib/maps-osm.c
+++ b/lib/maps-osm.c
@@ -69,12 +69,12 @@ parse_tag (const xmlAttr *attrs, GHashTable *tags)
 
   key = NULL;
   value = NULL;
-  
+
   for (cur_attr = attrs; cur_attr; cur_attr = cur_attr->next)
     {
-      if (g_str_equal (cur_attr->name, "k"))
+      if (g_str_equal ((const char *) cur_attr->name, "k"))
         key = (char *) cur_attr->children->content;
-      else if (g_str_equal (cur_attr->name, "v"))
+      else if (g_str_equal ((const char *) cur_attr->name, "v"))
         value = (char *) cur_attr->children->content;
       else
         g_warning ("Unexpected tag property: %s\n", cur_attr->name);
@@ -115,7 +115,7 @@ parse_tags (const xmlNode *tag_child)
       if (cur_node->type != XML_ELEMENT_NODE)
         continue;
 
-      if (g_str_equal (cur_node->name, "tag"))
+      if (g_str_equal ((const char *) cur_node->name, "tag"))
         parse_tag (cur_node->properties, tags);
     }
 
@@ -136,7 +136,7 @@ parse_node_refs (const xmlNode *node_ref_child)
       if (cur_node->type != XML_ELEMENT_NODE)
         continue;
 
-      if (g_str_equal (cur_node->name, "nd"))
+      if (g_str_equal ((const char *) cur_node->name, "nd"))
         {
           char *ref;
           GHashTable *attributes;
@@ -332,7 +332,7 @@ parse_members (const xmlNode *member_child)
       if (cur_node->type != XML_ELEMENT_NODE)
         continue;
 
-      if (g_str_equal (cur_node->name, "member"))
+      if (g_str_equal ((const char *) cur_node->name, "member"))
         {
           GHashTable *attributes;
 
@@ -452,15 +452,15 @@ maps_osm_parse (const char *content, guint length, GError **error)
       return NULL;
     }
 
-  if (g_str_equal (sub_node->name, "node"))
+  if (g_str_equal ((const char *) sub_node->name, "node"))
     {
       object = MAPS_OSMOBJECT (parse_node (sub_node, error));
     }
-  else if (g_str_equal (sub_node->name, "way"))
+  else if (g_str_equal ((const char *) sub_node->name, "way"))
     {
       object = MAPS_OSMOBJECT (parse_way (sub_node, error));
     }
-  else if (g_str_equal (sub_node->name, "relation"))
+  else if (g_str_equal ((const char *) sub_node->name, "relation"))
     {
       object = MAPS_OSMOBJECT (parse_relation (sub_node, error));
     }
@@ -495,7 +495,7 @@ maps_osm_parse_user_details (const char *content, GError **error)
       return NULL;
     }
 
-  if (g_str_equal (sub_node->name, "user"))
+  if (g_str_equal ((const char *) sub_node->name, "user"))
     {
       g_autoptr (GHashTable) attributes;