[libcxx-commits] [libcxx] [libc++] Fix ill-formed return in function_ref's static-call path (PR #228868)

[Yanzuo Liu via libcxx-commits]

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@@ -106,7 +106,10 @@ class function_ref<_Rp(_ArgTypes...) _LIBCPP_FUNCTION_REF_CV noexcept(__is_noexc
     using _Dn = remove_cv_t<_Tp>;
     if constexpr (__statically_callable<_Dn, __arg_t<_ArgTypes>...>) {
       __call_ = [](__storage_t, __arg_t<_ArgTypes>... __args) static noexcept(__is_noexcept) -> _Rp {
-        return _Dn::operator()(std::forward<__arg_t<_ArgTypes>>(__args)...);
+        if constexpr (is_void_v<_Rp>)
+          _Dn::operator()(std::forward<__arg_t<_ArgTypes>>(__args)...);
+        else
+          return _Dn::operator()(std::forward<__arg_t<_ArgTypes>>(__args)...);
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zwuis wrote:

No. `INVOKE<R>(...)` is `INVOKE(...)` **implicitly** converted to `R`.

https://github.com/llvm/llvm-project/pull/228868