8 files changed, 67 insertions, 6 deletions
diff --git a/mrbgems/mruby-compiler/core/codegen.c b/mrbgems/mruby-compiler/core/codegen.c
index 0c84dd558..39d62348a 100644
--- a/mrbgems/mruby-compiler/core/codegen.c
+++ b/mrbgems/mruby-compiler/core/codegen.c
@@ -1798,8 +1798,10 @@ codegen(codegen_scope *s, node *tree, int val)
         int pos;
 
         pop();
-        if (val && vsp >= 0) {
-          genop(s, MKOP_AB(OP_MOVE, vsp, cursp()));
+        if (val) {
+          if (vsp >= 0) {
+            genop(s, MKOP_AB(OP_MOVE, vsp, cursp()));
+          }
           pos = genop(s, MKOP_AsBx(name[0]=='|'?OP_JMPIF:OP_JMPNOT, cursp(), 0));
         }
         else {
diff --git a/mrbgems/mruby-string-ext/src/string.c b/mrbgems/mruby-string-ext/src/string.c
index 122ee5454..dfac907ec 100644
--- a/mrbgems/mruby-string-ext/src/string.c
+++ b/mrbgems/mruby-string-ext/src/string.c
@@ -23,10 +23,11 @@ static mrb_value
 mrb_str_setbyte(mrb_state *mrb, mrb_value str)
 {
   mrb_int pos, byte;
-  long len = RSTRING_LEN(str);
+  long len;
 
   mrb_get_args(mrb, "ii", &pos, &byte);
 
+  len = RSTRING_LEN(str);
   if (pos < -len || len <= pos)
     mrb_raisef(mrb, E_INDEX_ERROR, "index %S is out of array", mrb_fixnum_value(pos));
   if (pos < 0)
diff --git a/mrbgems/mruby-string-ext/test/string.rb b/mrbgems/mruby-string-ext/test/string.rb
index a5d55a7ee..228a236af 100644
--- a/mrbgems/mruby-string-ext/test/string.rb
+++ b/mrbgems/mruby-string-ext/test/string.rb
@@ -30,6 +30,18 @@ assert('String#setbyte') do
   assert_equal("Hello", str1)
 end
 
+assert("String#setbyte raises IndexError if arg conversion resizes String") do
+  $s = "01234\n"
+  class Tmp
+      def to_i
+          $s.chomp! ''
+          95
+      end
+  end
+  tmp = Tmp.new
+  assert_raise(IndexError) { $s.setbyte(5, tmp) }
+end
+
 assert('String#byteslice') do
   str1 = "hello"
   assert_equal("e", str1.byteslice(1))
diff --git a/mrbgems/mruby-struct/src/struct.c b/mrbgems/mruby-struct/src/struct.c
index 0ccb7f4cb..8c8f54f27 100644
--- a/mrbgems/mruby-struct/src/struct.c
+++ b/mrbgems/mruby-struct/src/struct.c
@@ -203,7 +203,7 @@ make_struct(mrb_state *mrb, mrb_value name, mrb_value members, struct RClass * k
     }
     if (mrb_const_defined_at(mrb, mrb_obj_value(klass), id)) {
       mrb_warn(mrb, "redefining constant Struct::%S", name);
-      /* ?rb_mod_remove_const(klass, mrb_sym2name(mrb, id)); */
+      mrb_const_remove(mrb, mrb_obj_value(klass), id);
     }
     c = mrb_define_class_under(mrb, klass, RSTRING_PTR(name), klass);
   }
diff --git a/mrbgems/mruby-struct/test/struct.rb b/mrbgems/mruby-struct/test/struct.rb
index 02ecf69e4..bbfe18cb2 100644
--- a/mrbgems/mruby-struct/test/struct.rb
+++ b/mrbgems/mruby-struct/test/struct.rb
@@ -158,3 +158,24 @@ assert("Struct#dig") do
   assert_equal 1, a.dig(:purple, :red)
   assert_equal 1, a.dig(1, 0)
 end
+
+assert("Struct.new removes existing constant") do
+  begin
+    assert_not_equal Struct.new("Test", :a), Struct.new("Test", :a, :b)
+  ensure
+    Struct.remove_const :Test
+  end
+end
+
+assert("Struct#initialize_copy requires struct to be the same type") do
+  begin
+    Struct.new("Test", :a)
+    a = Struct::Test.new("a")
+    Struct.new("Test", :a, :b)
+    assert_raise(TypeError) do
+      a.initialize_copy(Struct::Test.new("a", "b"))
+    end
+  ensure
+    Struct.remove_const :Test
+  end
+end
diff --git a/src/string.c b/src/string.c
index 5e490bf03..f47294291 100644
--- a/src/string.c
+++ b/src/string.c
@@ -1235,11 +1235,13 @@ mrb_str_chomp_bang(mrb_state *mrb, mrb_value str)
   char *p, *pp;
   mrb_int rslen;
   mrb_int len;
+  mrb_int argc;
   struct RString *s = mrb_str_ptr(str);
 
   mrb_str_modify(mrb, s);
+  argc = mrb_get_args(mrb, "|S", &rs);
   len = RSTR_LEN(s);
-  if (mrb_get_args(mrb, "|S", &rs) == 0) {
+  if (argc == 0) {
     if (len == 0) return mrb_nil_value();
   smart_chomp:
     if (RSTR_PTR(s)[len-1] == '\n') {
diff --git a/test/t/codegen.rb b/test/t/codegen.rb
new file mode 100644
index 000000000..f910d37fb
--- /dev/null
+++ b/test/t/codegen.rb
@@ -0,0 +1,11 @@
+##
+# Codegen tests
+
+assert('peephole optimization does not eliminate move whose result is reused') do
+  assert_raise LocalJumpError do
+    def method
+      yield
+    end
+    method(&a &&= 0)
+  end
+end
diff --git a/test/t/string.rb b/test/t/string.rb
index e67389b5c..80fcbe6fa 100644
--- a/test/t/string.rb
+++ b/test/t/string.rb
@@ -251,6 +251,19 @@ assert('String#chomp!', '15.2.10.5.10') do
   assert_equal 'abc', e
 end
 
+assert('String#chomp! uses the correct length') do
+  class A
+    def to_str
+      $s.replace("AA")
+      "A"
+    end
+  end
+
+  $s = "AAA"
+  $s.chomp!(A.new)
+  assert_equal $s, "A"
+end
+
 assert('String#chop', '15.2.10.5.11') do
   a = ''.chop
   b = 'abc'.chop
@@ -683,4 +696,3 @@ assert('String#freeze') do
 
   assert_raise(RuntimeError) { str.upcase! }
 end
-