[PATCH] D133202: [Clang] Avoid __builtin_assume_aligned crash when the 1st arg is array type

[Richard Smith - zygoloid via Phabricator via cfe-commits]

rsmith added inline comments.


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Comment at: clang/lib/Sema/SemaChecking.cpp:7651-7652
+  Expr *FirstArg = TheCall->getArg(0);
+  if (auto *CE = dyn_cast<CastExpr>(FirstArg))
+    FirstArg = CE->getSubExprAsWritten();
 
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This looks very suspicious to me: this will remove a cast expression that was written in the source code from the AST. That loses source fidelity, can give the wrong answer if the cast changed the value (such as a C++ derived-to-base conversion to a non-primary base class), and in any case this is only done once where there could be multiple explicit casts written on an argument to the builtin, so if it's necessary, then it's not being done fully.

Can this be removed?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D133202/new/

https://reviews.llvm.org/D133202