[PATCH] D92318: [llvm-readobj, libSupport] - Refine the implementation of the code that dumps build attributes.

[James Henderson via Phabricator via llvm-commits]

jhenderson added inline comments.


================
Comment at: llvm/tools/llvm-readobj/ELFDumper.cpp:2919-2920
 
-    // TODO: Delete the redundant FormatVersion check above.
-    if (Machine == EM_ARM) {
-      if (Error E = ARMAttributeParser(&W).parse(Contents, support::little))
-        reportWarning(std::move(E), ObjF.getFileName());
-    } else if (Machine == EM_RISCV) {
-      if (Error E = RISCVAttributeParser(&W).parse(Contents, support::little))
-        reportWarning(std::move(E), ObjF.getFileName());
-    }
+    Error E = Error::success();
+    consumeError(std::move(E));
+    if (Machine == EM_ARM)
----------------
grimar wrote:
> jhenderson wrote:
> > I think you can avoid this dance using the Error as output parameter idiom. See `ErrorAsOutParameter`.
> I am not sure I understood tthe idea. Are you saying that `parse` should accept an `Error` argument?
> `ErrorAsOutParameter` clears the checked bit in destructor. I wonder how it might help here.
> 
> I've replaced `consumeError` with `cantFail`.
Never mind, I misread the code. However, I have an alternative idea now: factor the `if (Machine == EM_ARM) ...` if statement and its corresponding else into a separat function/lambda, then return the Error so that you can do:

```
Error E = parseAttributes(...);
if (E)
  reportUniqueWarning(...);
```

What do you think?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D92318/new/

https://reviews.llvm.org/D92318