[PATCH] D63157: C++ DR712 and others: handle non-odr-use resulting from an lvalue-to-rvalue conversion applied to a member access or similar not-quite-trivial lvalue expression.

[John McCall via Phabricator via cfe-commits]

rjmccall added inline comments.


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Comment at: lib/CodeGen/CGExpr.cpp:1429
+/// for instance if a block or lambda or a member of a local class uses a
+/// const int variable or constexpr variable from an enclosing function.
 CodeGenFunction::ConstantEmission
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Isn't the old comment correct here?  This is mandatory because of the enclosing-local-scope issues; that might be an "optimization" in the language, but it's not an optimization at the IRGen level because Sema literally is forcing us to do it. 


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Comment at: lib/Sema/SemaExpr.cpp:15808
+namespace {
+// Helper to copy the template arguments from a DeclRefExpr or MemberExpr.
+class CopiedTemplateArgs {
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This is really cute; I might steal this idea.  That said, it's probably worth explaining the lifetime mechanics here so that non-experts can understand how this works.


Repository:
  rC Clang

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D63157/new/

https://reviews.llvm.org/D63157