[Mlir-commits] [mlir] [mlir][capi] make MLIR Pass C-API type safe (PR #121284)

[llvmlistbot at llvm.org]

SpriteOvO wrote:

> How does `ExternalPassCallbacks` construct?

See

https://github.com/llvm/llvm-project/blob/66dd7e63d8a1860c11f3b9acf011cad4e18f0195/mlir/test/CAPI/pass.c#L330-L336


> The `MlirExternalPass` is a struct that need to be construct from the C-API.

`MlirExternalPass` is an opaque struct defined here,

https://github.com/llvm/llvm-project/blob/6cbc64ed922cc69bc292d394ba5c681fa309f404/mlir/include/mlir-c/Pass.h#L44

you don't need to construct it, it will be an argument in your callback and you just use it as needed.

```c
void yourCallback(MlirOperation op, MlirExternalPass pass, void *userData) {
  if (anyError) {
    mlirExternalPassSignalFailure(pass);
  }
}
```

https://github.com/llvm/llvm-project/pull/121284