diff --git a/src/math_app.rs b/src/math_app.rs
index bae4cb7..1304b84 100644
--- a/src/math_app.rs
+++ b/src/math_app.rs
@@ -237,7 +237,7 @@ impl MathApp {
 			data
 		};
 
-		debug_assert!(data_decompressed.is_empty());
+		debug_assert!(!data_decompressed.is_empty());
 
 		unsafe {
 			assume(!data_decompressed.is_empty());