prevent null derefs found by scan-build

gfx/drivers/gl_core.c

@@ -503,7 +503,8 @@ static const gfx_ctx_driver_t *gl_core_get_context(gl_core_t *gl)
 #endif
 
    /* Force shared context. */
-   gl->use_shared_context = hwr->context_type != RETRO_HW_CONTEXT_NONE;
+   if (hwr)
+      gl->use_shared_context = hwr->context_type != RETRO_HW_CONTEXT_NONE;
 
    gfx_ctx = video_context_driver_init_first(gl,
          settings->arrays.video_context_driver,

libretro-common/net/net_http.c

@@ -483,15 +483,18 @@ struct http_t *net_http_new(struct http_connection_t *conn)
    return state;
 
 error:
-   if (conn->methodcopy)
-      free(conn->methodcopy);
-   if (conn->contenttypecopy)
-      free(conn->contenttypecopy);
-   conn->methodcopy = NULL;
-   conn->contenttypecopy = NULL;
-   conn->postdatacopy = NULL;
+   if (conn)
+   {
+      if (conn->methodcopy)
+         free(conn->methodcopy);
+      if (conn->contenttypecopy)
+         free(conn->contenttypecopy);
+      conn->methodcopy = NULL;
+      conn->contenttypecopy = NULL;
+      conn->postdatacopy = NULL;
+   }
 #ifdef HAVE_SSL
-   if (conn->sock_state.ssl && conn->sock_state.ssl_ctx && fd >= 0)
+   if (conn && conn->sock_state.ssl && conn->sock_state.ssl_ctx && fd >= 0)
    {
       ssl_socket_close(conn->sock_state.ssl_ctx);
       ssl_socket_free(conn->sock_state.ssl_ctx);

menu/cbs/menu_cbs_deferred_push.c

@@ -418,8 +418,9 @@ static int general_push(menu_displaylist_info_t *info,
             }
             else
             {
-               strlcpy(newstring2, system->valid_extensions,
-                     PATH_MAX_LENGTH * sizeof(char));
+               if (system)
+                  strlcpy(newstring2, system->valid_extensions,
+                        PATH_MAX_LENGTH * sizeof(char));
             }
          }
          break;
@@ -442,7 +443,7 @@ static int general_push(menu_displaylist_info_t *info,
             }
             else
             {
-               if (!string_is_empty(system->valid_extensions))
+               if (system && !string_is_empty(system->valid_extensions))
                {
                   new_exts           = strdup(system->valid_extensions);
                   new_exts_allocated = true;
@@ -473,7 +474,12 @@ static int general_push(menu_displaylist_info_t *info,
             }
 
             if (new_exts_allocated)
+            {
                free(new_exts);
+
+               if (new_exts == info->exts)
+                  info->exts = NULL;
+            }
          }
          break;
       case PUSH_ARCHIVE_OPEN_DETECT_CORE:

menu/cbs/menu_cbs_ok.c

@@ -3611,7 +3611,7 @@ finish:
             (transf ? transf->path: "unknown"), err);
    }
 #ifdef HAVE_DISCORD
-   else if (transf->enum_idx == MENU_ENUM_LABEL_CB_DISCORD_AVATAR)
+   else if (transf && transf->enum_idx == MENU_ENUM_LABEL_CB_DISCORD_AVATAR)
       discord_avatar_set_ready(true);
 #endif
 

menu/drivers/ozone/ozone.c

@@ -301,19 +301,23 @@ static void *ozone_init(void **userdata, bool video_is_threaded)
    return menu;
 
 error:
-   if (ozone->horizontal_list)
+   if (ozone)
    {
-      ozone_free_list_nodes(ozone->horizontal_list, false);
-      file_list_free(ozone->horizontal_list);
-   }
+      if (ozone->horizontal_list)
+      {
+         ozone_free_list_nodes(ozone->horizontal_list, false);
+         file_list_free(ozone->horizontal_list);
+      }
 
-   if (ozone->selection_buf_old)
-   {
-      ozone_free_list_nodes(ozone->selection_buf_old, false);
-      file_list_free(ozone->selection_buf_old);
+      if (ozone->selection_buf_old)
+      {
+         ozone_free_list_nodes(ozone->selection_buf_old, false);
+         file_list_free(ozone->selection_buf_old);
+      }
+
+      ozone->selection_buf_old = NULL;
+      ozone->horizontal_list   = NULL;
    }
-   ozone->selection_buf_old = NULL;
-   ozone->horizontal_list   = NULL;
 
    if (menu)
       free(menu);

menu/drivers/ozone/ozone_entries.c

@@ -441,7 +441,8 @@ void ozone_draw_entries(ozone_handle_t *ozone, video_frame_info_t *video_info,
       }
 
 border_iterate:
-      y += node->height;
+      if (node)
+         y += node->height;
    }
 
    /* Cursor(s) layer - current */

menu/menu_displaylist.c

@@ -2886,7 +2886,7 @@ static int menu_displaylist_parse_horizontal_content_actions(
    {
       const char *ext = NULL;
 
-      if (!string_is_empty(entry->path))
+      if (entry && !string_is_empty(entry->path))
          ext = path_get_extension(entry->path);
 
       if (!string_is_empty(ext) &&
@@ -2943,7 +2943,7 @@ static int menu_displaylist_parse_horizontal_content_actions(
       }
    }
 
-   if (!string_is_empty(entry->db_name) && (!content_loaded ||
+   if ((entry && !string_is_empty(entry->db_name)) && (!content_loaded ||
       (content_loaded && settings->bools.quick_menu_show_information)))
    {
       char *db_path = (char*)malloc(PATH_MAX_LENGTH * sizeof(char));
@@ -7782,7 +7782,7 @@ bool menu_displaylist_ctl(enum menu_displaylist_ctl_state type, menu_displaylist
                      PARSE_ACTION, false);
 
                /* Core fully loaded, use the subsystem data */
-               if (sys_info->subsystem.data)
+               if (sys_info && sys_info->subsystem.data)
                      subsystem = sys_info->subsystem.data;
                /* Core not loaded completely, use the data we peeked on load core */
                else