Adds a separate board for native64 instead of the `NATIVE_64BIT` workaround.
The files in `boards/native64` are more or less dummy files and just include
the `boards/native` logic (similar to `openlabs-kw41z-mini-256kib`).
The main logic for native is in `makefiles/arch/native.inc.mk`, `cpu/native`
and `boards/native`.
The remaining changes concern the build system, and change native board checks
to native CPU checks to cover both boards.
Initial version to test 64 bit compatibility.
Instead of a separate board, the inital version for Linux/x86_64 is enabled
by setting the environment variable `NATIVE_64BIT=y` and compiling as usual.
Not currently implemented:
* Architectures other than x86_64 or operating systems other than Linux
* No FreeBSD support
* No Aarch support
* Rust support for x86_64
Even Debian oldstable is now at glibc 2.28, so it is safe to assume that
nobody needs this anymore.
This also fixes garbage on the terminal on musl systems, where
`ldd --version` is not supported (and output on `stderr` was not
redirected to `/dev/null`).
This fixes the following warning on newer gcc/ld:
```
/usr/bin/ld: examples/hello-world/bin/native/cpu/tramp.o: warning: relocation against `_native_saved_eip' in read-only section `.text'
/usr/bin/ld: warning: creating DT_TEXTREL in a PIE
```
The standard is 9 years old now, it is well supported in all mayor compilers.
In fact, features of the 'new' standard are already used in RIOT (std_atomic).
Let's make it the default and adapt the Makefiles accordingly.
If `native` is compiled with `USEMODULE=socket_zep` and networking,
don't also include `netdev_tap` automatically.
This mirrors the behavior on nrf52 and esp* where the default netdev
can be 'overwritten' by another option.
With the introduction of BOARDSDIR external boards can re-use common
code of BOARDS present in RIOTBASE. To be able to do this file
references may not use $(BOARD) since BOARD will be set by the
external BOARD.
Without this change a RIOT application compiled with all-asan will
segfault as RIOT provides its own malloc by default. Add a define for
disabling custom malloc, calloc and realloc implementations and use it
when compiling with all-asan.
cpu/$(CPU)/Makefile.features and cpu/$(CPU)/Makefile.dep are
automatically included
Part of moving CPU/CPU_MODEL definition to Makefile.features to have it
available before Makefile.include.
