[PATCH] D157070: [C++20] [Coroutines] Introduce `@llvm.coro.opt.blocker` to block the may-be-incorrect optimization for awaiter

[Chuanqi Xu via Phabricator via llvm-commits]

ChuanqiXu added inline comments.


================
Comment at: clang/lib/CodeGen/CGCoroutine.cpp:158-169
+    assert(Result && "Why can't we find the record type from the common "
+                     "expression of a coroutine suspend expression? "
+                     "Maybe we missed some types or the Sema get something "
+                     "incorrect");
+
+    // In a release build without assertions enabled, return false directly
+    // to give users better user experience. It doesn't matter with the
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Note that the may cause a crash if there are some types we are not able to covered. This is intentional. Since such crash is easy to fix by adding new type to the TypeVisitor. I guess this may be understandable since the type system of clang frontend (or should I say C++?) is really complex.

Also note that this only matters with people who enabled assertions, possibly developers or testers.

For end users who use a clean release build, it is completely OK to not match the type. They **may** only need to pay 1 byte memory overhead. I feel this is better for the user experience.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D157070/new/

https://reviews.llvm.org/D157070