Is ArrayRef supposed to be immutable?

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#1

It seems like ArrayRefs are supposed to be immutable (
However, as far as i can tell, the iterators are defined wrong to make this true.

While
ArrayRef Foo(Something);
Foo[0] = 5;

will give a compile time error.

something like:

ArrayRef Foo(Something);
std::sort(Foo.begin(), Foo.end());

Will work fine.

Is this expected?

(FWIW: I expected this to only work with a MutableArrayRef)

#2

It wraps a constant T* and a size_t, so I’m surprised std::sort works. It shouldn’t.

#3

+1 seems like a bug

#4

+1, totally a bug. That’s the domain of MutableArrayRef.

-Chris

#5

It’s possible I’m missing something, but I can’t reproduce this:

std::vector A = { 4, 15, 42 , 16, 8, 23};
ArrayRef B(A);
std::sort(B.begin(), B.end());

fails to compile for me.

ArrayRef::iterator is specified as const T *, so I’m not seeing how this could happen?

#6

It's possible I'm missing something, but I can't reproduce this:

  std::vector<int> A = { 4, 15, 42 , 16, 8, 23};
  ArrayRef<int> B(A);
  std::sort(B.begin(), B.end());

fails to compile for me.

As later mentioned, it was transient and appears to have only affected some
version :slight_smile:
Because of that, i stopped looking into it after tracking it down to what
appears to be a hilarious miscompile of clang.