This PR defines a cross-compiler `DEPRECATED(message)` macro. It must
be used as follows in Rust:
```rust
/// This is a documentation.
/// cbindgen:prefix=DEPRECATED(This is a deprecation message.")
pub extern "C" fn wasmer_foo() -> c_uint {
42
}
```
It will generate the following C header:
```c
/**
* This is a documentation.
*/
DEPRECATED("This is a deprecation message.")
unsigned int wasmer_foo();
```
And once this code is used by a C compiler, it will print something
like this (example from Clang):
```
…/test.c:…:…: error: 'wasmer_foo' is deprecated: This is a deprecation message. [-Werror,-Wdeprecated-declarations]
unsigned int x = wasmer_foo();
^
…/wasmer.h:…:…: note: 'wasmer_foo' has been explicitly marked deprecated here
DEPRECATED("This is a deprecation message.")
^
…/wasmer.h:…:…: note: expanded from macro 'DEPRECATED'
```
This is required for further deprecations.
When the version has type `Version`, we expect the user to give a
valid `Version` variant. Since the `Version` is basically a `uint8_t`,
the user is able to pass everything she wants, which can create an
undefined behavior on the Rust side.
To avoid such situation, the version has now type `c_uchar` (`unsigned
char` or `uint8_t` on C side —on most platforms). Then the `From`
trait is implemented on `Version`. In case the value is unbound,
`Version::Unknown` is returned.
This patch updates `test-wasi-import-object` to test the new
`wasmer_wasi_get_version` &
`wasmer_wasi_generate_import_object_for_version` functions, and the
new `Version` type.
This patch introduces 2 new functions:
* `wasmer_wasi_generate_import_object_for_version` and
* `wasmer_wasi_get_version`.
It mimics the current API provided by `wasmer_wasi`, nothing fancy
here. It's just a regular port to C/C++.
Because `wasmer_wasi::get_wasi_version` returns an option, and in
order to simplify the C/C++ API, `wasmer_wasi_get_version` can return
`Version::Unknown` in case of an error. It's up to the user to check
the version is valid (i.e. not unknown).
914: Fix bug in getting a Memory from export in C API r=Hywan a=MarkMcCaskey
I believe this fixes the non-deterministic crashing on OSX in `go-ext-wasm`
Co-authored-by: Mark McCaskey <mark@wasmer.io>
