diff --git a/src/blitter/32bpp_base.cpp b/src/blitter/32bpp_base.cpp
index 1dc7e444fb..9d02ad8fa5 100644
--- a/src/blitter/32bpp_base.cpp
+++ b/src/blitter/32bpp_base.cpp
@@ -114,7 +114,7 @@ void Blitter_32bppBase::ScrollBuffer(void *video, int left, int top, int width,
 		/* Decrease height and increase top */
 		top += scroll_y;
 		height -= scroll_y;
-		assert(height > 0);
+		assert_msg(height > 0, "%d, %d, %d, %d, %d, %d", left, top, width, height, scroll_x, scroll_y);
 
 		/* Adjust left & width */
 		if (scroll_x >= 0) {
@@ -138,7 +138,7 @@ void Blitter_32bppBase::ScrollBuffer(void *video, int left, int top, int width,
 
 		/* Decrease height. (scroll_y is <=0). */
 		height += scroll_y;
-		assert(height > 0);
+		assert_msg(height > 0, "%d, %d, %d, %d, %d, %d", left, top, width, height, scroll_x, scroll_y);
 
 		/* Adjust left & width */
 		if (scroll_x >= 0) {