[PATCH] D28093: [ADT] Add a generic concatenating iterator and range.

[Eric Fiselier via Phabricator via llvm-commits]

EricWF requested changes to this revision.
EricWF added a reviewer: EricWF.
EricWF added inline comments.
This revision now requires changes to proceed.


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Comment at: include/llvm/ADT/STLExtras.h:477
+    // Build a sequence of functions to increment each iterator if possible.
+    auto IncrementHelperFns = {&concat_iterator::incrementHelper<Ns>...};
+
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EricWF wrote:
> If I'm not mistaken this deduces to `std::initializer_list<FuncType>`, and we shouldn't use `initializer_list` outside of performing initialization.
> 
> This should be changed to deduce as an array type instead (or any other sequenced container).
After double checking the standard I'm confident to say this code has UB; and should be fixed before committing.


https://reviews.llvm.org/D28093