[clang] [Clang][AArch64] Warn when calling streaming/non-streaming about vect… (PR #79842)

[Sander de Smalen via cfe-commits]

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@@ -7513,6 +7516,38 @@ void Sema::checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
       }
     }
 
+    auto *CallerFD = dyn_cast<FunctionDecl>(CurContext);
+    if (FD && CallerFD && Context.getTargetInfo().hasFeature("sme") &&
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sdesmalen-arm wrote:

This code requires that the function definition is available (`if (FD && ...)`), but the streaming mode is exposed through the interface, meaning that we shouldn't need `FD` in order to emit a diagnostic.

For example:
```
// I would expect a warning here.
void test_n_to_s(
    __SVInt32_t arg, void (*sc)(__SVInt32_t arg) __arm_streaming) {
  sc(arg);
}
```

https://github.com/llvm/llvm-project/pull/79842