hanchenye-llvm-project/clang/test/SemaCXX/decl-init-ref.cpp

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// RUN: %clang_cc1 -fsyntax-only -verify -std=c++0x %s
struct A {}; // expected-note {{candidate is the implicit copy constructor}}
struct BASE {
operator A(); // expected-note {{candidate function}}
};
struct BASE1 {
operator A(); // expected-note {{candidate function}}
};
class B : public BASE , public BASE1
{
public:
B();
} b;
extern B f();
const int& ri = (void)0; // expected-error {{reference to type 'int const' could not bind to an rvalue of type 'void'}}
int main() {
const A& rca = f(); // expected-error {{reference initialization of type 'struct A const &' with initializer of type 'class B' is ambiguous}}
Reimplement reference initialization (C++ [dcl.init.ref]) using the new notion of an "initialization sequence", which encapsulates the computation of the initialization sequence along with diagnostic information and the capability to turn the computed sequence into an expression. At present, I've only switched one CheckReferenceInit callers over to this new mechanism; more will follow. Aside from (hopefully) being much more true to the standard, the diagnostics provided by this reference-initialization code are a bit better than before. Some examples: p5-var.cpp:54:12: error: non-const lvalue reference to type 'struct Derived' cannot bind to a value of unrelated type 'struct Base' Derived &dr2 = b; // expected-error{{non-const lvalue reference to ... ^ ~ p5-var.cpp:55:9: error: binding of reference to type 'struct Base' to a value of type 'struct Base const' drops qualifiers Base &br3 = bc; // expected-error{{drops qualifiers}} ^ ~~ p5-var.cpp:57:15: error: ambiguous conversion from derived class 'struct Diamond' to base class 'struct Base': struct Diamond -> struct Derived -> struct Base struct Diamond -> struct Derived2 -> struct Base Base &br5 = diamond; // expected-error{{ambiguous conversion from ... ^~~~~~~ p5-var.cpp:59:9: error: non-const lvalue reference to type 'long' cannot bind to a value of unrelated type 'int' long &lr = i; // expected-error{{non-const lvalue reference to type ... ^ ~ p5-var.cpp:74:9: error: non-const lvalue reference to type 'struct Base' cannot bind to a temporary of type 'struct Base' Base &br1 = Base(); // expected-error{{non-const lvalue reference to ... ^ ~~~~~~ p5-var.cpp:102:9: error: non-const reference cannot bind to bit-field 'i' int & ir1 = (ib.i); // expected-error{{non-const reference cannot ... ^ ~~~~~~ p5-var.cpp:98:7: note: bit-field is declared here int i : 17; // expected-note{{bit-field is declared here}} ^ llvm-svn: 90992
2009-12-10 07:02:17 +08:00
A& ra = f(); // expected-error {{non-const lvalue reference to type 'struct A' cannot bind to a temporary of type 'class B'}}
}
struct PR6177 { A (&x)[1]; };
PR6177 x = {{A()}}; // expected-error{{non-const lvalue reference to type 'struct A [1]' cannot bind to a temporary of type 'struct A'}}