This reverts commit c28ac75a87.
This change caused SEGV in the case like the following:
```
class C
class << self
attr_accessor :a
alias :const_missing :a=
end
end
p C::CONST
```
The common parts of `OP_SEND` and `OP_SUPER` have been merged so they no longer need to be independent.
This effectively means revert commit d0e8637e30.
When `cipush()` extends "callinfo", GC may occur.
In this case, there was a problem that prepared arguments were spoiled depending on the situation when `cipush()` is called.
Therefore, in the problematic part, `cipush()` is prepared first, and then the arguments are prepared.
The reason for passing `CINFO_DIRECT` to `cipush()` is that it is simply ignored in the `MRB_CATCH()` part of `mrb_vm_exec()`.
Also, the argument processing parts of `mrb_funcall_with_block()` and `mrb_yield_with_class()` are combined and made independent as `funcall_args_capture()`.
Exception raising can now be controlled by the caller.
The main purpose on this patch is:
- Suppress exceptions from `obj_free()` in `src/gc.c` with `mrb_env_unshare()`.
- Consider the possibility that calls to `mrb_malloc()` may cause `e` objects to be subject to GC.
When control is returned to `mrb_env_unshare()`, `struct free_obj::next` in the same offset as `struct REnv::stack` is rewritten.
Unexpected results then occur when the object is reused.
Also, if `mrb_heap_page` containing an `e` object is freed, it may cause `SIGSEGV` at that point.
- Protects the value of the stack on `callinfo` that just exits if GC occurs inside `mrb_env_unshare()`.
```ruby
def m
b = -> { b }
end
p m.call
# => print block object, not nil
```
This patch does not raise a `NoMemoryError` exception in `mrb_env_unshare()` and can detect that error.
Thus, the problem fixed in # 3087 is not resurrected.
Also, it may seem that this patch should suppress exceptions raised by `cipop()` during `mrb_protect_error()` and `mrb_vm_exec()` unwinds.
However, `mrb_callinfo::u.env` by `CINFO_DIRECT` is not seen to be set.
So in that case `mrb_env_unshare()` is assumed to be originally exception-free.
- mrb_div_int() does integer division in Ruby way (mdiv)
returns mrb_int
- mrb_div_int_value() division with zero div and overflow checks.
returns mrb_value
When compiling mruby with `-DMRB_USE_CXX_EXCEPTION`, clang fails to
compile and emits these warnings:
vendor/mruby/src/vm.c:3066:1: error: extraneous closing brace ('}')
} /* end of extern "C" */
^
vendor/mruby/src/vm.c:3072:7: error: expected '}'
#endif
^
vendor/mruby/src/vm.c:3070:12: note: to match this '{'
extern "C" {
^
2 errors generated.
Fixup the implementation of the `extern "C"` block in `vm.c`.
Unlike `hash_new_from_regs`, `ary_new_from_regs` do not call
`mrb_funcall` et al directly or indirectly. But since it may invoke the
garbage collection, and hooks for GC may call `mrb_funcall` etc (although
calling them is not encouraged), we care stack reallocation just for the
safety.
Internal functions can only be called from within the library.
Functions listed in `mruby/internal.h` can be called from:
* core (src/*.c)
* gems (mrbgems/**/*.c)
But not from the application linked with `libmruby`.
Yukihiro "Matz" Matsumoto