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// RUN: rm -fR %t
// RUN: split-file %s %t
// RUN: cd %t
// RUN: %clang_cc1 -std=c++20 -emit-header-unit -xc++-user-header -Werror=uninitialized folly-conv.h
// RUN: %clang_cc1 -std=c++20 -emit-header-unit -xc++-user-header -Werror=uninitialized thrift_cpp2_base.h
// RUN: %clang_cc1 -std=c++20 -emit-header-unit -xc++-user-header -Werror=uninitialized -fmodule-file=folly-conv.pcm -fmodule-file=thrift_cpp2_base.pcm logger_base.h
//--- Conv.h
#pragma once
template <typename _Tp, typename _Up = _Tp&&>
_Up __declval(int);
template <typename _Tp>
auto declval() noexcept -> decltype(__declval<_Tp>(0));
namespace folly {
template <class Value, class Error>
struct Expected {
template <class Yes>
auto thenOrThrow() -> decltype(declval<Value&>()) {
return 1;
}
};
struct ExpectedHelper {
template <class Error, class T>
static constexpr Expected<T, Error> return_(T) {
return Expected<T, Error>();
}
template <class This, class Fn, class E = int, class T = ExpectedHelper>
static auto then_(This&&, Fn&&)
-> decltype(T::template return_<E>((declval<Fn>()(true), 0))) {
return Expected<int, int>();
}
};
template <class Tgt>
inline Expected<Tgt, const char*> tryTo() {
Tgt result = 0;
// In build with asserts:
// clang/lib/Sema/SemaTemplateInstantiate.cpp: llvm::PointerUnion<Decl *, LocalInstantiationScope::DeclArgumentPack *> *clang::LocalInstantiationScope::findInstantiationOf(const Decl *): Assertion `isa<LabelDecl>(D) && "declaration not instantiated in this scope"' failed.
// In release build compilation error on the line below inside lambda:
// error: variable 'result' is uninitialized when used here [-Werror,-Wuninitialized]
ExpectedHelper::then_(Expected<bool, int>(), [&](bool) { return result; });
return {};
}
} // namespace folly
inline void bar() {
folly::tryTo<int>();
}
// expected-no-diagnostics
//--- folly-conv.h
#pragma once
#include "Conv.h"
// expected-no-diagnostics
//--- thrift_cpp2_base.h
#pragma once
#include "Conv.h"
// expected-no-diagnostics
//--- logger_base.h
#pragma once
import "folly-conv.h";
import "thrift_cpp2_base.h";
inline void foo() {
folly::tryTo<unsigned>();
}
// expected-no-diagnostics
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