Since `cxt->ci` points to the last active callinfo, `cxt->ci == cxt->cibase`
does not mean it does not have correct `proc` information, so we have
removed the `f->cxt->ci > f->cxt->cibase` check. Instead, just in case
`proc` does not have `irep` information, we try to confirm `proc` does not
point to `CFUNC` nor is not an alias.
It is now possible to specify return destination directly.
This allows callinfo to distinguish between calls to the same proc object.
At the same time, the `Kernel#catch` method is adjusted.
By removing the previously required double lambda object, the REnv object is no longer created as well.
Since it is confusing that the term `mrbc` stands for both "mruby
compiler" and "mruby compiler context" in the source code. Instead,
we use `mrb_ccontext` (stands for compiler context) prefix hereafter.
We choose `mrb_ccontext` because we have already used `mrb_context` (for
VM execusion context).
When a fiber switched by `Fiber.yield` is resumed by `Fiber#resume` by C, it is necessary to pop CI with `fiber_switch()`.
Previously, CI misalignment caused inconsistencies, including crashes, on the next `Fiber#resume`.
If `mrb_fiber_resume()` was called from a C function as a method definition, the mruby VM was not processed afterwards.
Called Fiber.yield
mrb_vm_exec() <<-- returns from the function by CINFO_RESUMED
fiber_switch() <<-- this patch causes the value to return to its pre-call state
mrb_fiber_resume()
mrb_vm_exec() <<-- previously, returns from the function immediately as it was CINFO_RESUMED
...
main()
The main objective is to make sure that fiber can be handled from C.
Also, add a mechanism to detect that the mruby VM has stopped in the middle of the process.
If it stops halfway, the test will be terminated with `abort()`.
If the filename and line number cannot be obtained, "(unknown):1" is used instead.
Also, the file name information of the terminated fiber cannot be retrieved and will be replaced as well.
This limitation is due to the fact that `cibase->proc` of the terminated fiber is collected by the GC.
```console
% bin/mruby -e 'p Fiber.new { p Fiber.current }.resume'
#<Fiber:0x82423bef0 -e:1 (resumed)>
#<Fiber:0x82423bef0 (unknown):1 (terminated)>
```
The last commit changed the behavior of aliases, and we no longer keep
the alias name symbol but the original name. Since this is a small
incompatibility from CRuby and it requires some memory to fix this, we
keep this issue right now.
Since `Env` objects are shared by Blocks/Procs in the same context,
making multiple aliases in one context screws up with alias names.
New implementation uses alias bodies (Procs) to refer new names.
As a side effect, `__callee__` stop working correctly for aliases.
To fix this `__callee__` problem, we need to keep alias method names in
`callinfo`, which consumes more memory. We are wondering that is worth
the compatibility.
dearblue