diff --git a/include/fat32/FAT32_SYS.inc b/include/fat32/FAT32_SYS.inc
index 27f5add..e8b8365 100644
--- a/include/fat32/FAT32_SYS.inc
+++ b/include/fat32/FAT32_SYS.inc
@@ -302,6 +302,7 @@ NextCluster:
 .error_cfdivz:
     ERROR STAGE2_FAT32_NCLUS_CFDIVZ
 
+; clobbers eax, edx
 ; __fastcall16 uint32_t ClusterToLBA(uint32_t cluster)
 ; input = dword cluster in eax
 ALIGN 4, db 0x90