[PATCH] D140803: [clang][Interp] Implement C++ Range-for loops

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


================
Comment at: clang/lib/AST/Interp/ByteCodeStmtGen.cpp:404-409
+  if (Cond) {
+    if (!this->visitBool(Cond))
+      return false;
+    if (!this->jumpFalse(EndLabel))
+      return false;
+  }
----------------
Under what circumstances is there not a condition for a range-based for loop?


================
Comment at: clang/lib/AST/Interp/ByteCodeStmtGen.cpp:418-419
+  this->emitLabel(IncLabel);
+  if (Inc && !this->discard(Inc))
+    return false;
+  if (!this->jump(CondLabel))
----------------
Under what circumstances is there not an increment?


================
Comment at: clang/test/AST/Interp/loops.cpp:278
+
+namespace RangeForLoop {
+  constexpr int localArray() {
----------------
You should also add failure tests where the range-based for loop is not valid in a constant expression. Especially interesting cases would be ones involving lifetime problems, such as: https://godbolt.org/z/3EE7f8rdE


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D140803/new/

https://reviews.llvm.org/D140803