diff --git a/aegisub/src/resolution_resampler.cpp b/aegisub/src/resolution_resampler.cpp
index d63956ade..fbc179963 100644
--- a/aegisub/src/resolution_resampler.cpp
+++ b/aegisub/src/resolution_resampler.cpp
@@ -67,7 +67,8 @@ namespace {
 			}
 		}
 
-		final.pop_back();
+		if (final.size())
+			final.pop_back();
 		return final;
 	}