diff --git a/tests/test_badblocks.toml b/tests/test_badblocks.toml
index b600d231..01f23a08 100644
--- a/tests/test_badblocks.toml
+++ b/tests/test_badblocks.toml
@@ -31,7 +31,7 @@ defines.BADBLOCK_BEHAVIOR = [
 defines.CKPROGS = 'BADBLOCK_BEHAVIOR >= LFS_EMUBD_BADBLOCK_READERROR'
 defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512]
 # maximize lookahead buffer to avoid alloc scans
-defines.LOOKAHEAD_SIZE = 'lfs_alignup(BLOCK_COUNT / 8, 8)'
+defines.LOOKAHEAD_SIZE = '(BLOCK_COUNT+8-1) / 8'
 defines.SEED = 42
 fuzz = 'SEED'
 if = 'LFS_IFDEF_CKPROGS(true, !CKPROGS)'
@@ -1985,7 +1985,7 @@ defines.CKPROGS = 'BADBLOCK_BEHAVIOR >= LFS_EMUBD_BADBLOCK_READERROR'
 defines.MIRROR = [false, true]
 defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512]
 # maximize lookahead buffer to avoid alloc scans
-defines.LOOKAHEAD_SIZE = 'lfs_alignup(BLOCK_COUNT / 8, 8)'
+defines.LOOKAHEAD_SIZE = '(BLOCK_COUNT+8-1) / 8'
 defines.SEED = 42
 fuzz = 'SEED'
 if = 'LFS_IFDEF_CKPROGS(true, !CKPROGS)'
@@ -3942,7 +3942,7 @@ defines.CKPROGS = 'BADBLOCK_BEHAVIOR >= LFS_EMUBD_BADBLOCK_READERROR'
 defines.MIRROR = [false, true]
 defines.N = [1, 2, 4, 8, 16, 32, 64, 128, 256, 512]
 # maximize lookahead buffer to avoid alloc scans
-defines.LOOKAHEAD_SIZE = 'lfs_alignup(BLOCK_COUNT / 8, 8)'
+defines.LOOKAHEAD_SIZE = '(BLOCK_COUNT+8-1) / 8'
 defines.SEED = 42
 fuzz = 'SEED'
 if = 'LFS_IFDEF_CKPROGS(true, !CKPROGS)'
diff --git a/tests/test_btree.toml b/tests/test_btree.toml
index db5cddce..82826b81 100644
--- a/tests/test_btree.toml
+++ b/tests/test_btree.toml
@@ -3,7 +3,7 @@ after = 'test_rbyd'
 
 # maximize lookahead buffer, we don't actually gc so we only get one pass
 # of the disk for these tests
-defines.LOOKAHEAD_SIZE = 'lfs_alignup(BLOCK_COUNT / 8, 8)'
+defines.LOOKAHEAD_SIZE = '(BLOCK_COUNT+8-1) / 8'
 
 # test an empty tree
 [cases.test_btree_zero]
diff --git a/tests/test_mtree.toml b/tests/test_mtree.toml
index 35bfdd95..be796f8d 100644
--- a/tests/test_mtree.toml
+++ b/tests/test_mtree.toml
@@ -3,7 +3,7 @@ after = ['test_rbyd', 'test_btree']
 
 # maximize lookahead buffer, we don't actually gc so we only get one pass
 # of the disk for these tests
-defines.LOOKAHEAD_SIZE = 'BLOCK_COUNT / 8'
+defines.LOOKAHEAD_SIZE = '(BLOCK_COUNT+8-1) / 8'
 
 # test with normal revision counts, debug revision counts, and noisy
 # revision counts