string.c: `mrb_str_to_cstr()` should always return a mutable string.
MODIFY
src/string.c
src/string.c
@@ -835,8 +835,15 @@ mrb_str_to_cstr(mrb_state *mrb, mrb_value str0)
{
struct RString *s;
+ const char *p = RSTRING_PTR(str0);
+ size_t len = RSTRING_LEN(str0);
check_null_byte(mrb, str0);
- s = str_new(mrb, RSTRING_PTR(str0), RSTRING_LEN(str0));
+ if (RSTR_EMBEDDABLE_P(len)) {
+ s = str_init_embed(mrb_obj_alloc_string(mrb), p, len);
+ }
+ else {
+ s = str_init_normal(mrb, mrb_obj_alloc_string(mrb), p, len);
+ }
return RSTR_PTR(s);
}

string.c: `mrb_str_to_cstr()` should always return a mutable string.