diff --git a/lib/srfi/33/bit.c b/lib/srfi/33/bit.c
index 046d779e..0546cc33 100644
--- a/lib/srfi/33/bit.c
+++ b/lib/srfi/33/bit.c
@@ -157,7 +157,7 @@ static sexp sexp_arithmetic_shift (sexp ctx, sexp self, sexp_sint_t n, sexp i, s
   if (c == 0) return i;
   if (sexp_fixnump(i)) {
     if (c < 0) {
-      res = sexp_make_fixnum(sexp_unbox_fixnum(i) >> -c);
+      res = sexp_make_fixnum(c > -sizeof(sexp_sint_t)*CHAR_BIT ? sexp_unbox_fixnum(i) >> -c : 0);
     } else {
 #if SEXP_USE_BIGNUMS
       if ((log2i(sexp_unbox_fixnum(i)) + c + 1)
diff --git a/tests/srfi-33-tests.scm b/tests/srfi-33-tests.scm
index 74eb74d8..d314bd4a 100644
--- a/tests/srfi-33-tests.scm
+++ b/tests/srfi-33-tests.scm
@@ -34,4 +34,8 @@
 (test (- (expt 2 128)) (arithmetic-shift -1 128))
 (test (- (expt 2 129)) (arithmetic-shift -1 129))
 
+(test 0 (arithmetic-shift 1 -63))
+(test 0 (arithmetic-shift 1 -64))
+(test 0 (arithmetic-shift 1 -65))
+
 (test-end)