diff --git a/src/segment.c b/src/segment.c
index 869e05a8..bea43210 100644
--- a/src/segment.c
+++ b/src/segment.c
@@ -332,6 +332,8 @@ static uint8_t* _mi_segment_page_start_from_slice(const mi_segment_t* segment, c
     if (block_size <= 64) { start_offset += 3*block_size; }
     else if (block_size <= 512) { start_offset += block_size; }
   }
+  mi_assert_internal(_mi_is_aligned(pstart + start_offset, MI_MAX_ALIGN_SIZE));
+  mi_assert_internal(block_size == 0 || block_size > MI_MAX_ALIGN_GUARANTEE || _mi_is_aligned(pstart + start_offset,block_size));
   if (page_size != NULL) { *page_size = psize - start_offset; }
   return (pstart + start_offset);
 }
@@ -360,8 +362,6 @@ static size_t mi_segment_calculate_slices(size_t required, size_t* info_slices)
       required = _mi_align_up(required, MI_SEGMENT_SLICE_SIZE) + page_size;
     }
   }
-  mi_assert_internal(_mi_is_aligned(p, MI_MAX_ALIGN_SIZE));
-  mi_assert_internal(block_size > MI_MAX_ALIGN_GUARANTEE || _mi_is_aligned(p,block_size));
 
   isize = _mi_align_up(isize + guardsize, MI_SEGMENT_SLICE_SIZE);
   if (info_slices != NULL) *info_slices = isize / MI_SEGMENT_SLICE_SIZE;