diff --git a/src/diff.c b/src/diff.c
index 70e2814..ebe409e 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -1803,7 +1803,10 @@
 	    {
 		for (i = idx_orig; i < idx_new; ++i)
 		    if (curtab->tp_diffbuf[i] != NULL)
+		    {
 			dp->df_lnum[i] -= off;
+			dp->df_count[i] += off;
+		    }
 		dp->df_lnum[idx_new] = hunk->lnum_new;
 		dp->df_count[idx_new] = hunk->count_new;
 	    }
@@ -1815,9 +1818,7 @@
 	    }
 	    else
 		// second overlap of new block with existing block
-		dp->df_count[idx_new] += hunk->count_new - hunk->count_orig
-		    + dpl->df_lnum[idx_orig] + dpl->df_count[idx_orig]
-		    - (dp->df_lnum[idx_orig] + dp->df_count[idx_orig]);
+		dp->df_count[idx_new] += hunk->count_new;
 
 	    // Adjust the size of the block to include all the lines to the
 	    // end of the existing block or the new diff, whatever ends last.
@@ -1825,10 +1826,8 @@
 			 - (dpl->df_lnum[idx_orig] + dpl->df_count[idx_orig]);
 	    if (off < 0)
 	    {
-		// new change ends in existing block, adjust the end if not
-		// done already
-		if (notset)
-		    dp->df_count[idx_new] += -off;
+		// new change ends in existing block, adjust the end
+		dp->df_count[idx_new] += -off;
 		off = 0;
 	    }
 	    for (i = idx_orig; i < idx_new; ++i)