diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
index 99bd9f06..6846bcb2 100644
--- a/ext/bigdecimal/bigdecimal.c
+++ b/ext/bigdecimal/bigdecimal.c
@@ -5123,6 +5123,7 @@ VpNmlz(Real *a)
 NoVal:
     a->frac[0] = 0;
     a->Prec = 1;
+    a->exponent = 0;
     return 0;
 }
 
@@ -6007,7 +6008,7 @@ VpMidRound(Real *y, unsigned short f, ssize_t nf)
 	y->frac[ix] = div;
 	VpNmlz(y);
     }
-    if (exptoadd > 0) {
+    if (exptoadd > 0 && !VpIsZero(y)) {
 	y->exponent += (SIGNED_VALUE)(exptoadd / BASE_FIG);
 	exptoadd %= (ssize_t)BASE_FIG;
 	for (i = 0; i < exptoadd; i++) {
diff --git a/ext/bigdecimal/bigdecimal.h b/ext/bigdecimal/bigdecimal.h
index faa66264..46fb36b1 100644
--- a/ext/bigdecimal/bigdecimal.h
+++ b/ext/bigdecimal/bigdecimal.h
@@ -267,21 +267,21 @@ VP_EXPORT inline BDVALUE rbd_allocate_struct_zero_wrap(int sign, size_t const di
 #define VpIsPosZero(a)  ((a)->sign==VP_SIGN_POSITIVE_ZERO)
 #define VpIsNegZero(a)  ((a)->sign==VP_SIGN_NEGATIVE_ZERO)
 #define VpIsZero(a)     (VpIsPosZero(a) || VpIsNegZero(a))
-#define VpSetPosZero(a) ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_POSITIVE_ZERO)
-#define VpSetNegZero(a) ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_NEGATIVE_ZERO)
+#define VpSetPosZero(a) ((a)->frac[0]=0,(a)->Prec=1,(a)->exponent=0,(a)->sign=VP_SIGN_POSITIVE_ZERO)
+#define VpSetNegZero(a) ((a)->frac[0]=0,(a)->Prec=1,(a)->exponent=0,(a)->sign=VP_SIGN_NEGATIVE_ZERO)
 #define VpSetZero(a,s)  (void)(((s)>0)?VpSetPosZero(a):VpSetNegZero(a))
 
 /* NaN */
 #define VpIsNaN(a)      ((a)->sign==VP_SIGN_NaN)
-#define VpSetNaN(a)     ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_NaN)
+#define VpSetNaN(a)     ((a)->frac[0]=0,(a)->Prec=1,(a)->exponent=0,(a)->sign=VP_SIGN_NaN)
 
 /* Infinity */
 #define VpIsPosInf(a)   ((a)->sign==VP_SIGN_POSITIVE_INFINITE)
 #define VpIsNegInf(a)   ((a)->sign==VP_SIGN_NEGATIVE_INFINITE)
 #define VpIsInf(a)      (VpIsPosInf(a) || VpIsNegInf(a))
 #define VpIsDef(a)      ( !(VpIsNaN(a)||VpIsInf(a)) )
-#define VpSetPosInf(a)  ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_POSITIVE_INFINITE)
-#define VpSetNegInf(a)  ((a)->frac[0]=0,(a)->Prec=1,(a)->sign=VP_SIGN_NEGATIVE_INFINITE)
+#define VpSetPosInf(a)  ((a)->frac[0]=0,(a)->Prec=1,(a)->exponent=0,(a)->sign=VP_SIGN_POSITIVE_INFINITE)
+#define VpSetNegInf(a)  ((a)->frac[0]=0,(a)->Prec=1,(a)->exponent=0,(a)->sign=VP_SIGN_NEGATIVE_INFINITE)
 #define VpSetInf(a,s)   (void)(((s)>0)?VpSetPosInf(a):VpSetNegInf(a))
 #define VpHasVal(a)     (a->frac[0])
 #define VpIsOne(a)      ((a->Prec==1)&&(a->frac[0]==1)&&(a->exponent==1))
diff --git a/ext/bigdecimal/div.h b/ext/bigdecimal/div.h
index a171a471..c2160a3d 100644
--- a/ext/bigdecimal/div.h
+++ b/ext/bigdecimal/div.h
@@ -60,14 +60,10 @@ divmod_by_inv_mul(VALUE x, VALUE y, VALUE inv, VALUE *res_div, VALUE *res_mod) {
 static void
 slice_copy(DECDIG *dest, Real *src, size_t rshift, size_t length) {
     ssize_t start = src->exponent - (ssize_t)rshift - (ssize_t)length;
-    if (start >= (ssize_t)src->Prec) return;
-    if (start < 0) {
-        dest -= start;
-        length -= (size_t)(-start);
-        start = 0;
-    }
-    size_t max_length = (size_t)((ssize_t)src->Prec - start);
-    memcpy(dest, src->frac + start, Min(length, max_length) * sizeof(DECDIG));
+    ssize_t from = Max(start, 0);
+    ssize_t to = Min(start + (ssize_t)length, (ssize_t)src->Prec);
+    if (from >= to) return;
+    memcpy(dest + (from - start), src->frac + from, (size_t)(to - from) * sizeof(DECDIG));
 }
 
 /* Calculates divmod using Newton-Raphson method.
@@ -162,11 +158,8 @@ VpDivdNewtonInner(VALUE args_ptr)
     r2 = GetBDValueMust(mod);
     VpAsgn(c, c2.real, VpGetSign(a) * VpGetSign(b));
     VpAsgn(r, r2.real, VpGetSign(a));
-    AddExponent(c, a->exponent);
-    AddExponent(c, -b->exponent);
-    AddExponent(c, -(ssize_t)div_prec);
-    AddExponent(r, a->exponent);
-    AddExponent(r, -(ssize_t)(base_prec + div_prec));
+    if (!VpIsZero(c)) AddExponent(c, a->exponent - b->exponent - (ssize_t)div_prec);
+    if (!VpIsZero(r)) AddExponent(r, a->exponent - (ssize_t)(base_prec + div_prec));
     RB_GC_GUARD(a2.bigdecimal);
     RB_GC_GUARD(b2.bigdecimal);
     RB_GC_GUARD(c2.bigdecimal);
diff --git a/test/bigdecimal/test_vp_operation.rb b/test/bigdecimal/test_vp_operation.rb
index ce690aee..eea63b5e 100644
--- a/test/bigdecimal/test_vp_operation.rb
+++ b/test/bigdecimal/test_vp_operation.rb
@@ -182,6 +182,17 @@ def test_vpdivd_large_prec_divisor
     assert_vpdivd_equal([divy2_2, x - y2 * divy2_2], [x, y2, 2])
   end
 
+  def test_vpdivd_zero_quotient_block
+    # The last block of the quotient is zero and x * inv is far below 1.
+    # Copying that zero quotient wrote outside of the result buffer.
+    y = BigDecimal(7 * BASE + 1)
+    x = y * BASE**3 + 5
+    assert_vpdivd_equal([BigDecimal(BASE**3), BigDecimal(5)], [x, y, 4])
+    y = BigDecimal(10**1000 + 7)
+    x = y * BigDecimal("1e1800") + 5
+    assert_equal([BigDecimal("1e1800"), BigDecimal(5)], x.divmod(y))
+  end
+
   def test_vpdivd_intermediate_zero
     x = BigDecimal('123456789.246913578000000000123456789')
     y = BigDecimal('123456789')