[PATCH] D155064: [clang][SemaCXX] Diagnose tautological uses of consteval if and is_constant_evaluated

[Christopher Di Bella via Phabricator via cfe-commits]

cjdb added inline comments.


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Comment at: clang/test/SemaCXX/warn-constant-evaluated-constexpr.cpp:38
 constexpr int fn5() {
-  if constexpr (__builtin_is_constant_evaluated()) // expected-warning {{'__builtin_is_constant_evaluated' will always evaluate to 'true' in a manifestly constant-evaluated expression}}
+  if constexpr (__builtin_is_constant_evaluated()) // expected-warning {{'__builtin_is_constant_evaluated' will always evaluate to true in this context}}
     return 0;
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This should also generate a fix-it hint, since we can automate the fix.


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Comment at: clang/test/SemaCXX/warn-tautological-meta-constant.cpp:18
+  } else {
+    if constexpr (std::is_constant_evaluated()) { // expected-warning {{always evaluate to true}}
+      return 0;
----------------
I'm not a fan of this diagnostic text: it doesn't offer insight into what's gone wrong or provide actionable feedback on how to fix the code.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D155064/new/

https://reviews.llvm.org/D155064