diff --git a/eval.c b/eval.c
index 9c5dcb8659..f5344815ae 100644
--- a/eval.c
+++ b/eval.c
@@ -139,7 +139,7 @@ rb_secure(level)
 }
 
 void
-rb_check_safe_str(x)
+rb_check_safe_obj(x)
     VALUE x;
 {
     if (ruby_safe_level > 0 && OBJ_TAINTED(x)){
@@ -152,6 +152,13 @@ rb_check_safe_str(x)
 	}
     }
     rb_secure(4);
+}
+
+void
+rb_check_safe_str(x)
+    VALUE x;
+{
+    rb_check_safe_obj(x);
     if (TYPE(x)!= T_STRING) {
 	rb_raise(rb_eTypeError, "wrong argument type %s (expected String)",
 		 rb_obj_classname(x));
diff --git a/ext/dl/dl.c b/ext/dl/dl.c
index bfdf5e81a6..95bc780e07 100644
--- a/ext/dl/dl.c
+++ b/ext/dl/dl.c
@@ -24,8 +24,8 @@ rb_dl_scan_callback_args(long stack[], const char *proto,
   VALUE val;
 
   sp = stack;
-  for( i=1; proto[i]; i++ ){
-    switch( proto[i] ){
+  for (i=1; proto[i]; i++) {
+    switch (proto[i]) {
     case 'C':
       {
 	char v;
@@ -162,11 +162,11 @@ dlsizeof(const char *cstr)
 
   len  = strlen(cstr);
   size = 0;
-  for( i=0; i<len; i++ ){
+  for (i=0; i<len; i++) {
     n = 1;
-    if( isdigit(cstr[i+1]) ){
+    if (isdigit(cstr[i+1])) {
       dlen = 1;
-      while( isdigit(cstr[i+dlen]) ){ dlen ++; };
+      while (isdigit(cstr[i+dlen])) { dlen ++; };
       dlen --;
       d = ALLOCA_N(char, dlen + 1);
       strncpy(d, cstr + i + 1, dlen);
@@ -177,7 +177,7 @@ dlsizeof(const char *cstr)
       dlen = 0;
     }
 
-    switch( cstr[i] ){
+    switch (cstr[i]) {
     case 'I':
       DLALIGN(0,size,INT_ALIGN);
     case 'i':
@@ -234,9 +234,9 @@ c_farray(VALUE v, long *size)
   len = RARRAY(v)->len;
   *size = sizeof(float) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
     case T_FLOAT:
       ary[i] = (float)(RFLOAT(e)->value);
       break;
@@ -262,9 +262,9 @@ c_darray(VALUE v, long *size)
   len = RARRAY(v)->len;
   *size = sizeof(double) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
     case T_FLOAT:
       ary[i] = (double)(RFLOAT(e)->value);
       break;
@@ -290,9 +290,9 @@ c_larray(VALUE v, long *size)
   len = RARRAY(v)->len;
   *size = sizeof(long) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
     case T_FIXNUM:
     case T_BIGNUM:
       ary[i] = (long)(NUM2INT(e));
@@ -319,9 +319,9 @@ c_iarray(VALUE v, long *size)
   len = RARRAY(v)->len;
   *size = sizeof(int) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
     case T_FIXNUM:
     case T_BIGNUM:
       ary[i] = (int)(NUM2INT(e));
@@ -348,9 +348,9 @@ c_harray(VALUE v, long *size)
   len = RARRAY(v)->len;
   *size = sizeof(short) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
     case T_FIXNUM:
     case T_BIGNUM:
       ary[i] = (short)(NUM2INT(e));
@@ -377,9 +377,9 @@ c_carray(VALUE v, long *size)
   len = RARRAY(v)->len;
   *size = sizeof(char) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
     case T_FIXNUM:
     case T_BIGNUM:
       ary[i] = (char)(NUM2INT(e));
@@ -401,15 +401,23 @@ c_parray(VALUE v, long *size)
 {
   int i, len;
   void **ary;
-  VALUE e;
+  VALUE e, tmp;
 
   len = RARRAY(v)->len;
   *size = sizeof(void*) * len;
   ary = dlmalloc(*size);
-  for( i=0; i < len; i++ ){
+  for (i=0; i < len; i++) {
     e = rb_ary_entry(v, i);
-    switch( TYPE(e) ){
+    switch (TYPE(e)) {
+    default:
+      tmp = rb_check_string_type(e);
+      if (NIL_P(tmp)) {
+	  rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
+      }
+      e = tmp;
+      /* fall through */
     case T_STRING:
+      rb_check_safe_str(e);
       {
 	char *str, *src;
 	src = RSTRING(e)->ptr;
@@ -421,7 +429,7 @@ c_parray(VALUE v, long *size)
       ary[i] = NULL;
       break;
     case T_DATA:
-      if( rb_obj_is_kind_of(e, rb_cDLPtrData) ){
+      if (rb_obj_is_kind_of(e, rb_cDLPtrData)) {
 	struct ptr_data *pdata;
 	Data_Get_Struct(e, struct ptr_data, pdata);
 	ary[i] = (void*)(pdata->ptr);
@@ -430,9 +438,6 @@ c_parray(VALUE v, long *size)
 	rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
       }
       break;
-    default:
-      rb_raise(rb_eDLTypeError, "unexpected type of the element #%d", i);
-      break;
     }
   }
 
@@ -445,24 +450,26 @@ rb_ary2cary(char t, VALUE v, long *size)
   int len;
   VALUE val0;
 
-  if( TYPE(v) != T_ARRAY ){
+  val0 = rb_check_array_type(v);
+  if(NIL_P(TYPE(val0))) {
     rb_raise(rb_eDLTypeError, "an array is expected.");
   }
+  v = val0;
 
   len = RARRAY(v)->len;
-  if( len == 0 ){
+  if (len == 0) {
     return NULL;
   }
 
-  if( !size ){
+  if (!size) {
     size = ALLOCA_N(long,1);
   }
 
   val0 = rb_ary_entry(v,0);
-  switch( TYPE(val0) ){
+  switch (TYPE(val0)) {
   case T_FIXNUM:
   case T_BIGNUM:
-    switch( t ){
+    switch (t) {
     case 'C': case 'c':
       return (void*)c_carray(v,size);
     case 'H': case 'h':
@@ -477,7 +484,7 @@ rb_ary2cary(char t, VALUE v, long *size)
   case T_STRING:
     return (void*)c_parray(v,size);
   case T_FLOAT:
-    switch( t ){
+    switch (t) {
     case 'F': case 'f':
       return (void*)c_farray(v,size);
     case 'D': case 'd': case 0:
@@ -485,7 +492,7 @@ rb_ary2cary(char t, VALUE v, long *size)
     }
     rb_raise(rb_eDLTypeError, "type mismatch");
   case T_DATA:
-    if( rb_obj_is_kind_of(val0, rb_cDLPtrData) ){
+    if (rb_obj_is_kind_of(val0, rb_cDLPtrData)) {
       return (void*)c_parray(v,size);
     }
     rb_raise(rb_eDLTypeError, "type mismatch");
@@ -516,7 +523,7 @@ rb_ary_to_ptr(int argc, VALUE argv[], VALUE self)
   VALUE t;
   long size;
 
-  switch( rb_scan_args(argc, argv, "01", &t) ){
+  switch (rb_scan_args(argc, argv, "01", &t)) {
   case 1:
     ptr = rb_ary2cary(StringValuePtr(t)[0], self, &size);
     break;
@@ -556,15 +563,13 @@ rb_dl_malloc(VALUE self, VALUE size)
 VALUE
 rb_dl_strdup(VALUE self, VALUE str)
 {
-  rb_secure(4);
-  str = rb_String(str);
+  SafeStringValue(str);
   return rb_dlptr_new(strdup(RSTRING(str)->ptr), RSTRING(str)->len, dlfree);
 }
 
 static VALUE
 rb_dl_sizeof(VALUE self, VALUE str)
 {
-  rb_secure(4);
   return INT2NUM(dlsizeof(StringValuePtr(str)));
 }
 
@@ -577,9 +582,9 @@ rb_dl_callback(int argc, VALUE argv[], VALUE self)
 
   rb_secure(4);
   proc = Qnil;
-  switch( rb_scan_args(argc, argv, "11", &type, &proc) ){
+  switch (rb_scan_args(argc, argv, "11", &type, &proc)) {
   case 1:
-    if( rb_block_given_p() ){
+    if (rb_block_given_p()) {
       proc = rb_f_lambda();
     }
     else{
@@ -589,8 +594,8 @@ rb_dl_callback(int argc, VALUE argv[], VALUE self)
     break;
   }
 
-  Check_Type(type, T_STRING);
-  switch( RSTRING(type)->ptr[0] ){
+  StringValue(type);
+  switch (RSTRING(type)->ptr[0]) {
   case '0':
     rettype = 0x00;
     break;
@@ -620,13 +625,13 @@ rb_dl_callback(int argc, VALUE argv[], VALUE self)
   }
 
   entry = -1;
-  for( i=0; i < MAX_CALLBACK; i++ ){
-    if( rb_hash_aref(DLFuncTable, rb_assoc_new(INT2NUM(rettype), INT2NUM(i))) == Qnil ){
+  for (i=0; i < MAX_CALLBACK; i++) {
+    if (rb_hash_aref(DLFuncTable, rb_assoc_new(INT2NUM(rettype), INT2NUM(i))) == Qnil) {
       entry = i;
       break;
     }
   }
-  if( entry < 0 ){
+  if (entry < 0) {
     rb_raise(rb_eDLError, "too many callbacks are defined.");
   }
 
@@ -646,9 +651,9 @@ rb_dl_remove_callback(VALUE mod, VALUE sym)
 
   rb_secure(4);
   f = rb_dlsym2csym(sym);
-  for( i=0; i < CALLBACK_TYPES; i++ ){
-    for( j=0; j < MAX_CALLBACK; j++ ){
-      if( rb_dl_callback_table[i][j] == f ){
+  for (i=0; i < CALLBACK_TYPES; i++) {
+    for (j=0; j < MAX_CALLBACK; j++) {
+      if (rb_dl_callback_table[i][j] == f) {
 	rb_hash_aset(DLFuncTable, rb_assoc_new(INT2NUM(i),INT2NUM(j)),Qnil);
 	break;
       }
diff --git a/ext/dl/handle.c b/ext/dl/handle.c
index 23ad5ef066..17e8e5221d 100644
--- a/ext/dl/handle.c
+++ b/ext/dl/handle.c
@@ -10,7 +10,7 @@ VALUE rb_cDLHandle;
 void
 dlhandle_free(struct dl_handle *dlhandle)
 {
-  if( dlhandle->ptr && dlhandle->open && dlhandle->enable_close ){
+  if (dlhandle->ptr && dlhandle->open && dlhandle->enable_close) {
     dlclose(dlhandle->ptr);
   }
 }
@@ -50,7 +50,7 @@ rb_dlhandle_initialize(int argc, VALUE argv[], VALUE self)
   int   cflag;
   const char *err;
 
-  switch( rb_scan_args(argc, argv, "11", &lib, &flag) ){
+  switch (rb_scan_args(argc, argv, "11", &lib, &flag)) {
   case 1:
     clib = StringValuePtr(lib);
     cflag = RTLD_LAZY | RTLD_GLOBAL;
@@ -65,24 +65,24 @@ rb_dlhandle_initialize(int argc, VALUE argv[], VALUE self)
 
   ptr = dlopen(clib, cflag);
 #if defined(HAVE_DLERROR)
-  if( !ptr && (err = dlerror()) ){
+  if (!ptr && (err = dlerror())) {
     rb_raise(rb_eRuntimeError, err);
   }
 #else
-  if( !ptr ){
+  if (!ptr) {
     err = dlerror();
     rb_raise(rb_eRuntimeError, err);
   }
 #endif
   Data_Get_Struct(self, struct dl_handle, dlhandle);
-  if( dlhandle->ptr && dlhandle->open && dlhandle->enable_close ){
+  if (dlhandle->ptr && dlhandle->open && dlhandle->enable_close) {
     dlclose(dlhandle->ptr);
   }
   dlhandle->ptr = ptr;
   dlhandle->open = 1;
   dlhandle->enable_close = 0;
 
-  if( rb_block_given_p() ){
+  if (rb_block_given_p()) {
     rb_ensure(rb_yield, self, rb_dlhandle_close, self);
   }
 
@@ -138,14 +138,16 @@ rb_dlhandle_sym(int argc, VALUE argv[], VALUE self)
   const char *name, *stype;
   const char *err;
 
-  if( rb_scan_args(argc, argv, "11", &sym, &type) == 2 ){
+  rb_secure(4);
+  if (rb_scan_args(argc, argv, "11", &sym, &type) == 2) {
+    SafeStringValue(type);
     stype = StringValuePtr(type);
   }
   else{
     stype = NULL;
   }
 
-  if( sym == Qnil ){
+  if (sym == Qnil) {
 #if defined(RTLD_NEXT)
     name = RTLD_NEXT;
 #else
@@ -153,21 +155,22 @@ rb_dlhandle_sym(int argc, VALUE argv[], VALUE self)
 #endif
   }
   else{
+    SafeStringValue(sym);
     name = StringValuePtr(sym);
   }
 
 
   Data_Get_Struct(self, struct dl_handle, dlhandle);
-  if( ! dlhandle->open ){
+  if (! dlhandle->open) {
     rb_raise(rb_eRuntimeError, "Closed handle.");
   }
   handle = dlhandle->ptr;
 
   func = dlsym(handle, name);
 #if defined(HAVE_DLERROR)
-  if( !func && (err = dlerror()) )
+  if (!func && (err = dlerror()))
 #else
-  if( !func )
+  if (!func)
 #endif
   {
 #if defined(__CYGWIN__) || defined(WIN32) || defined(__MINGW32__)
@@ -180,9 +183,9 @@ rb_dlhandle_sym(int argc, VALUE argv[], VALUE self)
       func = dlsym(handle, name_a);
       dlfree(name_a);
 #if defined(HAVE_DLERROR)
-      if( !func && (err = dlerror()) )
+      if (!func && (err = dlerror()))
 #else
-      if( !func )
+      if (!func)
 #endif
       {
 	rb_raise(rb_eRuntimeError, "Unknown symbol \"%sA\".", name);
diff --git a/ext/dl/ptr.c b/ext/dl/ptr.c
index a7a9aebbd6..1eb0b82730 100644
--- a/ext/dl/ptr.c
+++ b/ext/dl/ptr.c
@@ -33,7 +33,7 @@ rb_dlmem_delete(void *ptr)
 static void
 rb_dlmem_aset(void *ptr, VALUE obj)
 {
-  if( obj == Qnil ){
+  if (obj == Qnil) {
     rb_dlmem_delete(ptr);
   }
   else{
@@ -53,22 +53,22 @@ rb_dlmem_aref(void *ptr)
 void
 dlptr_free(struct ptr_data *data)
 {
-  if( data->ptr ){
+  if (data->ptr) {
     DEBUG_CODE({
       printf("dlptr_free(): removing the pointer `0x%x' from the MemorySpace\n",
 	     data->ptr);
     });
     rb_dlmem_delete(data->ptr);
-    if( data->free ){
+    if (data->free) {
       DEBUG_CODE({
 	printf("dlptr_free(): 0x%x(data->ptr:0x%x)\n",data->free,data->ptr);
       });
       (*(data->free))(data->ptr);
     }
   }
-  if( data->stype ) dlfree(data->stype);
-  if( data->ssize ) dlfree(data->ssize);
-  if( data->ids  ) dlfree(data->ids);
+  if (data->stype) dlfree(data->stype);
+  if (data->ssize) dlfree(data->ssize);
+  if (data->ids) dlfree(data->ids);
 }
 
 void
@@ -82,6 +82,7 @@ dlptr_init(VALUE val)
 	   data->ptr);
   });
   rb_dlmem_aset(data->ptr, val);
+  OBJ_TAINT(val);
 }
 
 VALUE
@@ -91,9 +92,9 @@ rb_dlptr_new2(VALUE klass, void *ptr, long size, freefunc_t func)
   VALUE val;
 
   rb_secure(4);
-  if( ptr ){
+  if (ptr) {
     val = rb_dlmem_aref(ptr);
-    if( val == Qnil ){
+    if (val == Qnil) {
       val = Data_Make_Struct(klass, struct ptr_data,
 			     0, dlptr_free, data);
       data->ptr = ptr;
@@ -108,7 +109,7 @@ rb_dlptr_new2(VALUE klass, void *ptr, long size, freefunc_t func)
       dlptr_init(val);
     }
     else{
-      if( func ){
+      if (func) {
 	Data_Get_Struct(val, struct ptr_data, data);
 	data->free = func;
       }
@@ -144,11 +145,11 @@ rb_dlptr2cptr(VALUE val)
   struct ptr_data *data;
   void *ptr;
 
-  if( rb_obj_is_kind_of(val, rb_cDLPtrData) ){
+  if (rb_obj_is_kind_of(val, rb_cDLPtrData)) {
     Data_Get_Struct(val, struct ptr_data, data);
     ptr = data->ptr;
   }
-  else if( val == Qnil ){
+  else if (val == Qnil) {
     ptr = NULL;
   }
   else{
@@ -188,7 +189,7 @@ rb_dlptr_initialize(int argc, VALUE argv[], VALUE self)
   freefunc_t f = NULL;
   long s = 0;
 
-  switch( rb_scan_args(argc, argv, "12", &ptr, &size, &sym) ){
+  switch (rb_scan_args(argc, argv, "12", &ptr, &size, &sym)) {
   case 1:
     p = (void*)(DLNUM2LONG(rb_Integer(ptr)));
     break;
@@ -205,9 +206,9 @@ rb_dlptr_initialize(int argc, VALUE argv[], VALUE self)
     rb_bug("rb_dlptr_initialize");
   }
 
-  if( p ){
+  if (p) {
     Data_Get_Struct(self, struct ptr_data, data);
-    if( data->ptr && data->free ){
+    if (data->ptr && data->free) {
       /* Free previous memory. Use of inappropriate initialize may cause SEGV. */
       (*(data->free))(data->ptr);
     }
@@ -226,7 +227,7 @@ rb_dlptr_s_malloc(int argc, VALUE argv[], VALUE klass)
   int   s;
   freefunc_t f = NULL;
 
-  switch( rb_scan_args(argc, argv, "11", &size, &sym) ){
+  switch (rb_scan_args(argc, argv, "11", &size, &sym)) {
   case 1:
     s = NUM2INT(size);
     break;
@@ -313,14 +314,14 @@ rb_dlptr_to_array(int argc, VALUE argv[], VALUE self)
 
   Data_Get_Struct(self, struct ptr_data, data);
 
-  switch( rb_scan_args(argc, argv, "11", &type, &size) ){
+  switch (rb_scan_args(argc, argv, "11", &type, &size)) {
   case 2:
     t = StringValuePtr(type)[0];
     n = NUM2INT(size);
     break;
   case 1:
     t = StringValuePtr(type)[0];
-    switch( t ){
+    switch (t) {
     case 'C':
       n = data->size;
       break;
@@ -343,9 +344,9 @@ rb_dlptr_to_array(int argc, VALUE argv[], VALUE self)
       n = data->size / sizeof(void*);
       break;
     default:
-      if( t == 'p' || t == 's' ){
+      if (t == 'p' || t == 's') {
 	int i;
-	for( i=0; ((void**)(data->ptr))[i]; i++ ){};
+	for (i=0; ((void**)(data->ptr))[i]; i++) {};
 	n = i;
       }
       else{
@@ -359,8 +360,8 @@ rb_dlptr_to_array(int argc, VALUE argv[], VALUE self)
 
   ary = rb_ary_new();
 
-  for( i=0; i < n; i++ ){
-    switch( t ){
+  for (i=0; i < n; i++) {
+    switch (t) {
     case 'C':
       rb_ary_push(ary, INT2NUM(((char*)(data->ptr))[i]));
       break;
@@ -381,7 +382,7 @@ rb_dlptr_to_array(int argc, VALUE argv[], VALUE self)
     case 'S':
       {
 	char *str = ((char**)(data->ptr))[i];
-	if( str ){
+	if (str) {
 	  rb_ary_push(ary, rb_tainted_str_new2(str));
 	}
 	else{
@@ -392,7 +393,7 @@ rb_dlptr_to_array(int argc, VALUE argv[], VALUE self)
     case 's':
       {
 	char *str = ((char**)(data->ptr))[i];
-	if( str ){
+	if (str) {
 	  rb_ary_push(ary, rb_tainted_str_new2(str));
 	  xfree(str);
 	}
@@ -423,7 +424,7 @@ rb_dlptr_to_s(int argc, VALUE argv[], VALUE self)
   int len;
 
   Data_Get_Struct(self, struct ptr_data, data);
-  switch( rb_scan_args(argc, argv, "01", &arg1) ){
+  switch (rb_scan_args(argc, argv, "01", &arg1)) {
   case 0:
     val = rb_tainted_str_new2((char*)(data->ptr));
     break;
@@ -446,7 +447,7 @@ rb_dlptr_to_str(int argc, VALUE argv[], VALUE self)
   int len;
 
   Data_Get_Struct(self, struct ptr_data, data);
-  switch( rb_scan_args(argc, argv, "01", &arg1) ){
+  switch (rb_scan_args(argc, argv, "01", &arg1)) {
   case 0:
     val = rb_tainted_str_new((char*)(data->ptr),data->size);
     break;
@@ -527,16 +528,16 @@ rb_dlptr_define_data_type(int argc, VALUE argv[], VALUE self)
   rb_scan_args(argc, argv, "11*", &data_type, &type, &rest);
   Data_Get_Struct(self, struct ptr_data, data);
 
-  if( argc == 1 || (argc == 2 && type == Qnil) ){
-    if( NUM2INT(data_type) == DLPTR_CTYPE_UNKNOWN ){
+  if (argc == 1 || (argc == 2 && type == Qnil)) {
+    if (NUM2INT(data_type) == DLPTR_CTYPE_UNKNOWN) {
       data->ctype = DLPTR_CTYPE_UNKNOWN;
       data->slen = 0;
       data->ids_num  = 0;
-      if( data->stype ){
+      if (data->stype) {
 	dlfree(data->stype);
 	data->stype = NULL;
       }
-      if( data->ids ){
+      if (data->ids) {
 	dlfree(data->ids);
 	data->ids = NULL;
       }
@@ -551,32 +552,29 @@ rb_dlptr_define_data_type(int argc, VALUE argv[], VALUE self)
   StringValue(type);
   Check_Type(rest, T_ARRAY);
   num = RARRAY(rest)->len;
-  for( i=0; i<num; i++ ){
-    vid = rb_ary_entry(rest,i);
-    if( !(TYPE(vid)==T_STRING || TYPE(vid)==T_SYMBOL) ){
-      rb_raise(rb_eTypeError, "#%d must be a string or symbol", i + 2);
-    }
+  for (i=0; i<num; i++) {
+    rb_to_id(rb_ary_entry(rest,i));
   }
 
   data->ctype = t;
   data->slen = num;
   data->ids_num  = num;
-  if( data->stype ) dlfree(data->stype);
+  if (data->stype) dlfree(data->stype);
   data->stype = (char*)dlmalloc(sizeof(char) * num);
-  if( data->ssize ) dlfree(data->ssize);
+  if (data->ssize) dlfree(data->ssize);
   data->ssize = (int*)dlmalloc(sizeof(int) * num);
-  if( data->ids ) dlfree(data->ids);
+  if (data->ids) dlfree(data->ids);
   data->ids  = (ID*)dlmalloc(sizeof(ID) * data->ids_num);
 
   ctype = StringValuePtr(type);
-  for( i=0; i<num; i++ ){
+  for (i=0; i<num; i++) {
     vid = rb_ary_entry(rest,i);
     data->ids[i] = rb_to_id(vid);
     data->stype[i] = *ctype;
     ctype ++;
-    if( isdigit(*ctype) ){
+    if (isdigit(*ctype)) {
       char *p, *d;
-      for( p=ctype; isdigit(*p); p++ ) ;
+      for (p=ctype; isdigit(*p); p++) ;
       d = ALLOCA_N(char, p - ctype + 1);
       strncpy(d, ctype, p - ctype);
       d[p - ctype] = '\0';
@@ -588,11 +586,11 @@ rb_dlptr_define_data_type(int argc, VALUE argv[], VALUE self)
     }
   }
 
-  if( *ctype ){
+  if (*ctype) {
     rb_raise(rb_eArgError, "too few/many arguments");
   }
 
-  if( !data->size )
+  if (!data->size)
     data->size = dlsizeof(RSTRING(type)->ptr);
 
   return Qnil;
@@ -607,7 +605,7 @@ rb_dlptr_define_struct(int argc, VALUE argv[], VALUE self)
   pass_argc = argc + 1;
   pass_argv = ALLOCA_N(VALUE, pass_argc);
   pass_argv[0] = INT2FIX(DLPTR_CTYPE_STRUCT);
-  for( i=1; i<pass_argc; i++ ){
+  for (i=1; i<pass_argc; i++) {
     pass_argv[i] = argv[i-1];
   }
   return rb_dlptr_define_data_type(pass_argc, pass_argv, self);
@@ -622,7 +620,7 @@ rb_dlptr_define_union(int argc, VALUE argv[], VALUE self)
   pass_argc = argc + 1;
   pass_argv = ALLOCA_N(VALUE, pass_argc);
   pass_argv[0] = INT2FIX(DLPTR_CTYPE_UNION);
-  for( i=1; i<pass_argc; i++ ){
+  for (i=1; i<pass_argc; i++) {
     pass_argv[i] = argv[i-1];
   }
   return rb_dlptr_define_data_type(pass_argc, pass_argv, self);
@@ -634,7 +632,7 @@ rb_dlptr_get_data_type(VALUE self)
   struct ptr_data *data;
 
   Data_Get_Struct(self, struct ptr_data, data);
-  if( data->stype )
+  if (data->stype)
     return rb_assoc_new(INT2FIX(data->ctype),
 			rb_tainted_str_new(data->stype, data->slen));
   else
@@ -648,11 +646,11 @@ cary2ary(void *ptr, char t, int len)
   VALUE elem;
   int i;
 
-  if( len < 1 )
+  if (len < 1)
     return Qnil;
 
-  if( len == 1 ){
-    switch( t ){
+  if (len == 1) {
+    switch (t) {
     case 'I':
       elem = INT2NUM(*((int*)ptr));
       ptr = (char *)ptr + sizeof(int);
@@ -689,8 +687,8 @@ cary2ary(void *ptr, char t, int len)
   }
 
   ary = rb_ary_new();
-  for( i=0; i < len; i++ ){
-    switch( t ){
+  for (i=0; i < len; i++) {
+    switch (t) {
     case 'I':
       elem = INT2NUM(*((int*)ptr));
       ptr = (char *)ptr + sizeof(int);
@@ -738,28 +736,28 @@ rb_dlptr_aref(int argc, VALUE argv[], VALUE self)
   int i;
   int offset;
 
-  if( rb_scan_args(argc, argv, "11", &key, &num) == 1 ){
+  if (rb_scan_args(argc, argv, "11", &key, &num) == 1) {
     num = INT2NUM(0);
   }
 
-  if( TYPE(key) == T_FIXNUM || TYPE(key) == T_BIGNUM ){
+  if (TYPE(key) == T_FIXNUM || TYPE(key) == T_BIGNUM) {
     VALUE pass[1];
     pass[0] = num;
     return rb_dlptr_to_str(1, pass, rb_dlptr_plus(self, key));
   }
-
-  if( ! (TYPE(key) == T_STRING || TYPE(key) == T_SYMBOL ) ){
+  rb_to_id(key);
+  if (! (TYPE(key) == T_STRING || TYPE(key) == T_SYMBOL)) {
     rb_raise(rb_eTypeError, "the key must be a string or symbol");
   }
 
   id = rb_to_id(key);
   Data_Get_Struct(self, struct ptr_data, data);
   offset = 0;
-  switch( data->ctype ){
+  switch (data->ctype) {
   case DLPTR_CTYPE_STRUCT:
-    for( i=0; i < data->ids_num; i++ ){
-      if( data->ids[i] == id ){
-	switch( data->stype[i] ){
+    for (i=0; i < data->ids_num; i++) {
+      if (data->ids[i] == id) {
+	switch (data->stype[i]) {
 	case 'I':
 	  DLALIGN(data->ptr,offset,INT_ALIGN);
 	  break;
@@ -786,7 +784,7 @@ rb_dlptr_aref(int argc, VALUE argv[], VALUE self)
 	}
 	return cary2ary((char *)data->ptr + offset, data->stype[i], data->ssize[i]);
       }
-      switch( data->stype[i] ){
+      switch (data->stype[i]) {
       case 'I':
 	offset += sizeof(int) * data->ssize[i];
 	break;
@@ -815,8 +813,8 @@ rb_dlptr_aref(int argc, VALUE argv[], VALUE self)
     }
     break;
   case DLPTR_CTYPE_UNION:
-    for( i=0; i < data->ids_num; i++ ){
-      if( data->ids[i] == id ){
+    for (i=0; i < data->ids_num; i++) {
+      if (data->ids[i] == id) {
 	return cary2ary((char *)data->ptr + offset, data->stype[i], data->ssize[i]);
       }
     }
@@ -834,7 +832,7 @@ ary2cary(char t, VALUE val, long *size)
 {
   void *ptr;
 
-  if( TYPE(val) == T_ARRAY ){
+  if (TYPE(val) == T_ARRAY) {
     ptr = rb_ary2cary(t, val, size);
   }
   else{
@@ -855,14 +853,14 @@ rb_dlptr_aset(int argc, VALUE argv[], VALUE self)
   void *memimg;
 
   rb_secure(4);
-  switch( rb_scan_args(argc, argv, "21", &key, &num, &val) ){
+  switch (rb_scan_args(argc, argv, "21", &key, &num, &val)) {
   case 2:
     val = num;
     num = Qnil;
     break;
   }
 
-  if( TYPE(key) == T_FIXNUM || TYPE(key) == T_BIGNUM ){
+  if (TYPE(key) == T_FIXNUM || TYPE(key) == T_BIGNUM) {
     void *dst, *src;
     long len;
 
@@ -871,29 +869,25 @@ rb_dlptr_aset(int argc, VALUE argv[], VALUE self)
     dst = (void*)((long)(data->ptr) + DLNUM2LONG(key));
     src = RSTRING(val)->ptr;
     len = RSTRING(val)->len;
-    if( num == Qnil ){
+    if (num == Qnil) {
       memcpy(dst, src, len);
     }
     else{
       long n = NUM2INT(num);
       memcpy(dst, src, n < len ? n : len);
-      if( n > len ) MEMZERO((char*)dst + len, char, n - len);
+      if (n > len) MEMZERO((char*)dst + len, char, n - len);
     }
     return val;
   }
 
-  if( ! (TYPE(key) == T_STRING || TYPE(key) == T_SYMBOL ) ){
-    rb_raise(rb_eTypeError, "the key must be a string or symbol");
-  }
-
   id = rb_to_id(key);
   Data_Get_Struct(self, struct ptr_data, data);
-  switch( data->ctype ){
+  switch (data->ctype) {
   case DLPTR_CTYPE_STRUCT:
     offset = 0;
-    for( i=0; i < data->ids_num; i++ ){
-      if( data->ids[i] == id ){
-	switch( data->stype[i] ){
+    for (i=0; i < data->ids_num; i++) {
+      if (data->ids[i] == id) {
+	switch (data->stype[i]) {
 	case 'I':
 	  DLALIGN(data->ptr,offset,INT_ALIGN);
 	  break;
@@ -922,7 +916,7 @@ rb_dlptr_aset(int argc, VALUE argv[], VALUE self)
 	memcpy((char *)data->ptr + offset, memimg, memsize);
 	return val;
       }
-      switch( data->stype[i] ){
+      switch (data->stype[i]) {
       case 'I':
       case 'i':
 	offset += sizeof(int) * data->ssize[i];
@@ -960,9 +954,9 @@ rb_dlptr_aset(int argc, VALUE argv[], VALUE self)
     return val;
     /* break; */
   case DLPTR_CTYPE_UNION:
-    for( i=0; i < data->ids_num; i++ ){
-      if( data->ids[i] == id ){
-	switch( data->stype[i] ){
+    for (i=0; i < data->ids_num; i++) {
+      if (data->ids[i] == id) {
+	switch (data->stype[i]) {
 	case 'I': case 'i':
 	  memsize = sizeof(int) * data->ssize[i];
 	  break;
@@ -1007,7 +1001,7 @@ rb_dlptr_size(int argc, VALUE argv[], VALUE self)
 {
   VALUE size;
 
-  if( rb_scan_args(argc, argv, "01", &size) == 0){
+  if (rb_scan_args(argc, argv, "01", &size) == 0){
     return DLLONG2NUM(RDLPTR(self)->size);
   }
   else{
diff --git a/ext/dl/sym.c b/ext/dl/sym.c
index 7e18e61b5e..2034c0a7ff 100644
--- a/ext/dl/sym.c
+++ b/ext/dl/sym.c
@@ -330,7 +330,7 @@ rb_dlsym_call(int argc, VALUE argv[], VALUE self)
   long ftype;
   void *func;
 
-  rb_secure(4);
+  rb_secure(2);
   Data_Get_Struct(self, struct sym_data, sym);
   DEBUG_CODE({
     printf("rb_dlsym_call(): type = '%s', func = 0x%x\n", sym->type, sym->func);
@@ -457,20 +457,20 @@ rb_dlsym_call(int argc, VALUE argv[], VALUE self)
 	ANY2S(args[i]) = DLSTR(0);
       }
       else{
-	if( TYPE(argv[i]) != T_STRING ){
-	  rb_raise(rb_eDLError, "#%d must be a string",i);
-	}
-	ANY2S(args[i]) = DLSTR(RSTRING(argv[i])->ptr);
+	VALUE str = argv[i];
+	SafeStringValue(str);
+	ANY2S(args[i]) = DLSTR(RSTRING(str)->ptr);
       }
       PUSH_P(ftype);
       break;
     case 's':
-      if( TYPE(argv[i]) != T_STRING ){
-	rb_raise(rb_eDLError, "#%d must be a string",i);
+      {
+	VALUE str = argv[i];
+	SafeStringValue(str);
+	ANY2S(args[i]) = DLSTR(dlmalloc(RSTRING(str)->len + 1));
+	memcpy((char*)(ANY2S(args[i])), RSTRING(str)->ptr, RSTRING(str)->len + 1);
+	dtypes[i] = 's';
       }
-      ANY2S(args[i]) = DLSTR(dlmalloc(RSTRING(argv[i])->len + 1));
-      memcpy((char*)(ANY2S(args[i])), RSTRING(argv[i])->ptr, RSTRING(argv[i])->len + 1);
-      dtypes[i] = 's';
       PUSH_P(ftype);
       break;
     default:
diff --git a/lib/jcode.rb b/lib/jcode.rb
index ab6ab60701..8064518017 100644
--- a/lib/jcode.rb
+++ b/lib/jcode.rb
@@ -19,9 +19,9 @@ class String
   PATTERN_EUC = '[\xa1-\xfe][\xa1-\xfe]'
   PATTERN_UTF8 = '[\xc0-\xdf][\x80-\xbf]|[\xe0-\xef][\x80-\xbf][\x80-\xbf]'
 
-  RE_SJIS = Regexp.new(PATTERN_SJIS, 'n')
-  RE_EUC = Regexp.new(PATTERN_EUC, 'n')
-  RE_UTF8 = Regexp.new(PATTERN_UTF8, 'n')
+  RE_SJIS = Regexp.new(PATTERN_SJIS, 0, 'n')
+  RE_EUC = Regexp.new(PATTERN_EUC, 0, 'n')
+  RE_UTF8 = Regexp.new(PATTERN_UTF8, 0, 'n')
 
   SUCC = {}
   SUCC['s'] = Hash.new(1)
diff --git a/object.c b/object.c
index 5cfc3ed579..bef92c41c6 100644
--- a/object.c
+++ b/object.c
@@ -773,12 +773,14 @@ ID
 rb_to_id(name)
     VALUE name;
 {
+    VALUE tmp;
     ID id;
 
     switch (TYPE(name)) {
       case T_STRING:
 	return rb_intern(RSTRING(name)->ptr);
       case T_FIXNUM:
+	rb_warn("do not use Fixnums as Symbols");
 	id = FIX2LONG(name);
 	if (!rb_id2name(id)) {
 	    rb_raise(rb_eArgError, "%ld is not a symbol", id);
@@ -788,6 +790,10 @@ rb_to_id(name)
 	id = SYM2ID(name);
 	break;
       default:
+	tmp = rb_check_string_type(name);
+	if (!NIL_P(tmp)) {
+	    return rb_intern(RSTRING(tmp)->ptr);
+	}
 	rb_raise(rb_eTypeError, "%s is not a symbol", RSTRING(rb_inspect(name))->ptr);
     }
     return id;
diff --git a/ruby.h b/ruby.h
index 782838ed97..d1a371b4ee 100644
--- a/ruby.h
+++ b/ruby.h
@@ -215,12 +215,14 @@ VALUE rb_string_value _((volatile VALUE*));
 char *rb_string_value_ptr _((volatile VALUE*));
 
 #define StringValue(v) if (TYPE(v) != T_STRING) rb_string_value(&(v))
+#define StringValuePtr(v) rb_string_value_ptr(&(v))
+
+void rb_check_safe_obj _((VALUE));
 void rb_check_safe_str _((VALUE));
 #define SafeStringValue(v) do {\
     StringValue(v);\
-    rb_check_safe_str(v);\
+    rb_check_safe_obj(v);\
 } while (0)
-#define StringValuePtr(v) rb_string_value_ptr(&(v))
 /* obsolete macro - use SafeStringValue(v) */
 #define Check_SafeStr(v) rb_check_safe_str((VALUE)(v))
 
diff --git a/version.h b/version.h
index 41967ae0a8..1cb3c4fdf8 100644
--- a/version.h
+++ b/version.h
@@ -1,11 +1,11 @@
 #define RUBY_VERSION "1.8.0"
-#define RUBY_RELEASE_DATE "2003-03-23"
+#define RUBY_RELEASE_DATE "2003-03-24"
 #define RUBY_VERSION_CODE 180
-#define RUBY_RELEASE_CODE 20030323
+#define RUBY_RELEASE_CODE 20030324
 
 #define RUBY_VERSION_MAJOR 1
 #define RUBY_VERSION_MINOR 8
 #define RUBY_VERSION_TEENY 0
 #define RUBY_RELEASE_YEAR 2003
-#define RUBY_RELEASE_MONTH 03
-#define RUBY_RELEASE_DAY 23
+#define RUBY_RELEASE_MONTH 3
+#define RUBY_RELEASE_DAY 24