Cherry picks to release branch (#9230)

* [ios][macos] test remove source in use

* [android] test remove source in use

* [core] check source usage before remove

* [core] ensure layer::accept works with non-void return values on gcc

* [android] - remove upgrade runtime exceptions (#9191)

1 files changed, 7 insertions, 0 deletions

diff --git a/include/mbgl/style/layer.hpp b/include/mbgl/style/layer.hpp
index 56f2c48fa7..016b3a1c8b 100644
--- a/include/mbgl/style/layer.hpp
+++ b/include/mbgl/style/layer.hpp
@@ -5,8 +5,10 @@
 #include <mbgl/style/layer_type.hpp>
 #include <mbgl/style/types.hpp>
 
+#include <cassert>
 #include <memory>
 #include <string>
+#include <stdexcept>
 
 namespace mbgl {
 namespace style {
@@ -96,6 +98,11 @@ public:
         case LayerType::FillExtrusion:
             return visitor(*as<FillExtrusionLayer>());
         }
+
+
+        // Not reachable, but placate GCC.
+        assert(false);
+        throw new std::runtime_error("unknown layer type");
     }
 
     const std::string& getID() const;