diff --git a/src/filo-blockdev.adb b/src/filo-blockdev.adb
index 6581c40..8e3748e 100644
--- a/src/filo-blockdev.adb
+++ b/src/filo-blockdev.adb
@@ -21,6 +21,8 @@
    begin
       -- With 32-bit longs, the current C interface
       -- can't access more than 512 * 2 ** 32:
+      pragma Warnings (GNAT, Off, "condition can only be True if");
+      pragma Warnings (GNAT, Off, "condition is always False");
       if Unsigned_64 (Offset / BLOCK_SIZE) > Unsigned_64 (unsigned_long'last) then
          Success := False;
          return;