[core] Fix GCC8's new -Wcatch-value warnings

Polymorphic types shouldn't be caught by value, as the warning message says. Catch them by constant reference instead.

1 files changed, 1 insertions, 1 deletions

diff --git a/platform/default/mbgl/storage/offline_download.cpp b/platform/default/mbgl/storage/offline_download.cpp
index 1bd29f031c..4da51db655 100644
--- a/platform/default/mbgl/storage/offline_download.cpp
+++ b/platform/default/mbgl/storage/offline_download.cpp
@@ -355,7 +355,7 @@ void OfflineDownload::ensureResource(const Resource& resource,
             if (buffer.size() == 64 || resourcesRemaining.size() == 0) {
                 try {
                     offlineDatabase.putRegionResources(id, buffer, status);
-                } catch (MapboxTileLimitExceededException) {
+                } catch (const MapboxTileLimitExceededException&) {
                     onMapboxTileCountLimitExceeded();
                     return;
                 }