Static proc objects defined as methods may be placed in 4-byte alignments in 32-bit environments.
This may be misinterpreted as an immediate value depending on the address.
Since C11 and C++11 have additional language features for byte alignment, corresponding compilers use them to define the `mrb_alignas()` macro.
For earlier compilers, they use their own extensions to define the `mrb_alignas()` macro.
GCC supports `__attribute__((aligned(alignment)))` since at least version 2.95.3 (1999).
https://gcc.gnu.org/onlinedocs/gcc-2.95.3/gcc_4.html#IDX305
According to GPT-4, support was added in version 2.7 (1995).
It is not known which version of Visual C++ added support for `__declspec(align(n))`.
According to GPT-4, at least Visual C++ 6.0 (1998) seems to support it.
Also, the documentation of past Intel C/C++ compilers that support `__declspec(align(n))` makes reference to support with Visual C++ 4.2 (1996).
https://www.intel.com/content/dam/www/public/ijkk/jp/ja/documents/developer/ccomp40j.pdf
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.
The following methods will be made static.
- `Class#new`
- `Proc#call`
- `Kernel#catch`
Previously, static const RProc could not be registered as a method, but this has been changed to allow it.