- I(%d:%p) -> I[%d]
- L(%d) -> L[%d]
The irep address is not useful, so just print index in reps table.
And use `[]` instead of `()` to clarify they are index.
- mrb_clear_error(): clear error status of mrb_state
- mrb_check_error(): check if error caused in the previous API
Note that `mrb_check_error` clears error status, so if you call
`mrb_check_error` more than once, latter calls will return FALSE.
Move the detachment of the "env" object, now done by `mrb_top_run()` by #5904, to `mrb_vm_run()`.
This is because `mrb_vm_run()` can remove `mrb_env_unshare()` which is called from `bin/mirb`.
Also, even if the mruby VM is already running, either of the following conditions should be used to detach "env":
- If the `stack_keep` variable is 0.
- If the stack length of "env" is longer than `irep->nlocals`.
The reason for the change is that the stack beyond `irep->nlocals` is used inside the called method, and previously it was possible to reference and manipulate the state inside the method via "env".
env stack | |
main stack | top | m1 | m2 |
|<--------------->|
operable via env stack (including self)
If the problematic block is called from the `m2` method above, it is possible to replace `self` in `m1` and `m2` as well as the internal variables.
This change may cause compatibility problems, but I believe it is better to make `MRB_API`, `mrb_vm_run()` safe.
If a dangerous procedure is absolutely necessary, `mrb_vm_exec()` can still be called as before.
This is to keep the local variables of the previously created blocks consistent in case the `mrbc_context` passed to `mrb_load_exec()` is `NULL` or different.
Switching between `mrbc_context` pointers that are non `NULL` can be done safely by calling `mrbc_cleanup_local_variables()`.
Before this patch, the result of the following code is not as expected.
```console
% cat loadstr.c
#include <mruby.h>
#include <mruby/compile.h>
int
main(int argc, char *argv[])
{
mrb_state *mrb = mrb_open();
mrb_load_string(
mrb,
"(a, b, c, d, e, f, g) = [1, 2, 3, 4, 5, 6, 7] \n"
"$lambda = -> { p [a, b, c, d, e, f, g] }");
mrb_load_string(mrb, "$lambda.call");
mrb_close(mrb);
return 0;
}
% $(bin/mruby-config --cc --cflags --ldflags) loadstr.c $(bin/mruby-config --libs) && ./a.out
[main, nil, nil, main, nil, nil, main]
```
Also, since `mrb_env_unshare()` was not used before, the internal stack of simply detached `env` objects could show invalid addresses by `stack_extend()`.
ref. https://github.com/kou/mruby-pp/commit/ef5951aca870183d8767cb61f6414240988ca35e
It fixes a bug that instance_eval for immediate objects defines methods
in Object, instead of raising error.
```ruby
1.instance_eval do
def foo
p :foo
end
end
```
If pre-allocate object is modified (e.g. singleton class added) in
certain timing, some objects may be swept even if it's alive.
The problem was reported by Denis Kasak via private communication.
Yukihiro "Matz" Matsumoto