diff --git a/compile.c b/compile.c
index 341361dc78..d9894d27d8 100644
--- a/compile.c
+++ b/compile.c
@@ -2005,10 +2005,15 @@ cdhash_cmp(VALUE val, VALUE lit)
     else if (tlit == T_FLOAT) {
         return rb_float_cmp(lit, val);
     }
-    else if (tlit ==  T_RATIONAL) {
-        const struct RRational *dat1 = RRATIONAL(val);
-        const struct RRational *dat2 = RRATIONAL(lit);
-        return (dat1->num == dat2->num) && (dat1->den == dat2->den);
+    else if (tlit == T_RATIONAL) {
+        const struct RRational *rat1 = RRATIONAL(val);
+        const struct RRational *rat2 = RRATIONAL(lit);
+        return (rat1->num == rat2->num) && (rat1->den == rat2->den);
+    }
+    else if (tlit == T_COMPLEX) {
+        const struct RComplex *comp1 = RCOMPLEX(val);
+        const struct RComplex *comp2 = RCOMPLEX(lit);
+        return (comp1->real == comp2->real) && (comp1->imag == comp2->imag);
     }
     else {
         UNREACHABLE_RETURN(-1);
@@ -2030,6 +2035,8 @@ cdhash_hash(VALUE a)
         return rb_dbl_long_hash(RFLOAT_VALUE(a));
       case T_RATIONAL:
         return rb_rational_hash(a);
+      case T_COMPLEX:
+        return rb_complex_hash(a);
       default:
         UNREACHABLE_RETURN(0);
     }
diff --git a/complex.c b/complex.c
index fe8def28d1..66d9754331 100644
--- a/complex.c
+++ b/complex.c
@@ -1326,8 +1326,8 @@ nucomp_numerator(VALUE self)
 }
 
 /* :nodoc: */
-static VALUE
-nucomp_hash(VALUE self)
+st_index_t
+rb_complex_hash(VALUE self)
 {
     st_index_t v, h[2];
     VALUE n;
@@ -1338,7 +1338,13 @@ nucomp_hash(VALUE self)
     n = rb_hash(dat->imag);
     h[1] = NUM2LONG(n);
     v = rb_memhash(h, sizeof(h));
-    return ST2FIX(v);
+    return v;
+}
+
+static VALUE
+nucomp_hash(VALUE self)
+{
+    return ST2FIX(rb_complex_hash(self));
 }
 
 /* :nodoc: */
diff --git a/internal/complex.h b/internal/complex.h
index 6f63a9ebeb..9eae804ddb 100644
--- a/internal/complex.h
+++ b/internal/complex.h
@@ -25,5 +25,6 @@ struct RComplex {
 
 /* complex.c */
 VALUE rb_dbl_complex_new_polar_pi(double abs, double ang);
+st_index_t rb_complex_hash(VALUE comp);
 
 #endif /* INTERNAL_COMPLEX_H */
diff --git a/test/ruby/test_rational.rb b/test/ruby/test_rational.rb
index 5262b6edad..27d0527d42 100644
--- a/test/ruby/test_rational.rb
+++ b/test/ruby/test_rational.rb
@@ -839,6 +839,10 @@ class Rational_Test < Test::Unit::TestCase
       n = case 3/2r when 1.5r then true else false end
       assert_equal(n, true, '[ruby-core:103759] [Bug #17854]')
     RUBY
+    assert_separately([], <<-RUBY)
+      n = case 1i when 1i then true else false end
+      assert_equal(n, true, '[ruby-core:103759] [Bug #17854]')
+    RUBY
   end
 
   def test_Rational_with_invalid_exception