This pulls in adjustments to the C-nonbreaking but Rust-breaking API
change in https://github.com/RIOT-OS/RIOT/pull/17359
cstr_core is forcibly kept at 0.2.4 because 0.2.5 needs a newer nightly
than riotdocker currently has.
This adds a simple macro to check (at C level) whether a given
expression is proven to be compile time constant and suitable for
constant folding. This allows writing code like this:
```C
int gpio_read(gpio_t pin) {
if (IS_CT_CONSTANT(pin)) {
/* this implementation should even be able to use the port and
* pin number as immediate in inline assembly */
}
else {
/* less efficient implementation that cannot use port and pin
* number as immediate in inline assembly */
}
}
```
If module `arduino_serial_stdio` is used and `ARDUINO_UART_DEV` is `UART_UNDEF`, the STDIO is used for `Serial`. It requires that the used `stdio` backend implements `stdio_available`.
On ARM platforms, `__dso_handle` is used for dynamic shared objects. But it is also required if global static objects are used. To avoid that `sys/cpp11_compat` is required only for using the (re)defined `new`/`delete` operators, `__dso_handle` is moved to module `sys/cpp_new_delete`
The `new` and `delete` operators that don't need `libtsdc++` are also provided by module `sys/cpp_new_delete` for platforms that don't have the `libstdc++`. Since these operators in `sys/cpp11-compat` are just wrappers for standard `malloc`/`free` functions like in `sys/cpp_new_delete`, the `new`/`delete` operators that don't need `libstdc++` are used from `sys/cpp_new_delete`. Only the `new`/`delete` operators that require the `libstd++` are left in `sys/cpp11-compat`.
So it is sufficient for the use of the (re)defined `new`/`delete` operators that an application uses the module `sys/cpp_new_delete` instead of `sys/cpp11-compat` and thus also works on platforms without `libstdc++`.
This provides the same functionality as `static_assert()` provided by
C11 and has no advantages compared to it. Hence, encourage users to use
standard C functionality instead.
