diff --git a/src/ai/simulated_actions.cpp b/src/ai/simulated_actions.cpp
index ebcba3fe812..b7568df2154 100644
--- a/src/ai/simulated_actions.cpp
+++ b/src/ai/simulated_actions.cpp
@@ -250,7 +250,7 @@ void helper_advance_unit(const map_location& loc){
 		const unit_type *advanced_type = unit_types.find(advance_unit_typename);
 		if(!advanced_type) {
 			ERR_AI_SIM_ACTIONS << "Simulating advancing to unknown unit type: " << advance_unit_typename;
-			assert(false && "simulating to unknown unit type");
+			return;
 		}
 		advanced_unit->set_experience(advanced_unit->experience_overflow());
 		advanced_unit->advance_to(*advanced_type);
diff --git a/src/gui/core/canvas.cpp b/src/gui/core/canvas.cpp
index f7dfff9f61b..277196c9ee1 100644
--- a/src/gui/core/canvas.cpp
+++ b/src/gui/core/canvas.cpp
@@ -634,8 +634,6 @@ void canvas::parse_cfg(const config& cfg)
 		} else {
 			ERR_GUI_P << "Canvas: found a shape of an invalid type " << type
 					  << ".";
-
-			assert(false);
 		}
 	}
 }