143 lines
3.8 KiB
C++
143 lines
3.8 KiB
C++
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// RUN: %clang_cc1 -std=c++1z -verify %s
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// RUN: %clang_cc1 -std=c++1z -verify %s -DUNDEFINED
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#ifdef UNDEFINED
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// "used but not defined" errors don't get produced if we have more interesting
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// errors.
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namespace std_example {
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template <typename T, typename... Rest> void g(T &&p, Rest &&... rs) {
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// use p
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if constexpr(sizeof...(rs) > 0)
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g(rs...);
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}
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void use_g() {
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g(1, 2, 3);
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}
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static int x(); // no definition of x required
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int f() {
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if constexpr (true)
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return 0;
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else if (x())
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return x();
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else
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return -x();
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}
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}
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namespace odr_use_in_selected_arm {
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static int x(); // expected-warning {{is not defined}}
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int f() {
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if constexpr (false)
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return 0;
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else if (x()) // expected-note {{here}}
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return x();
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else
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return -x();
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}
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}
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#else
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namespace ccce {
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void f() {
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if (5) {}
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if constexpr (5) {} // expected-error {{cannot be narrowed}}
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}
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template<int N> void g() {
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if constexpr (N) {} // expected-error {{cannot be narrowed}}
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}
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template void g<5>(); // expected-note {{instantiation of}}
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void h() {
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if constexpr (4.3) {} // expected-error{{conversion from 'double' to 'bool' is not allowed in a converted constant expression}}
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constexpr void *p = nullptr;
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if constexpr (p) {} // expected-error{{conversion from 'void *const' to 'bool' is not allowed in a converted constant expression}}
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}
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}
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namespace generic_lambda {
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// Substituting for T produces a hard error here, even if substituting for
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// the type of x would remove the error.
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template<typename T> void f() {
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[](auto x) {
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if constexpr (sizeof(T) == 1 && sizeof(x) == 1)
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T::error(); // expected-error 2{{'::'}}
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} (0);
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}
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template<typename T> void g() {
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[](auto x) {
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if constexpr (sizeof(T) == 1)
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if constexpr (sizeof(x) == 1)
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T::error(); // expected-error {{'::'}}
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} (0);
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}
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void use() {
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f<int>(); // expected-note {{instantiation of}}
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f<char>(); // expected-note {{instantiation of}}
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g<int>(); // ok
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g<char>(); // expected-note {{instantiation of}}
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}
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}
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namespace potentially_discarded_branch_target {
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void in_switch(int n) {
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switch (n)
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case 4: if constexpr(sizeof(n) == 4) return;
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if constexpr(sizeof(n) == 4)
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switch (n) case 4: return;
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switch (n) {
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if constexpr (sizeof(n) == 4) // expected-note 2{{constexpr if}}
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case 4: return; // expected-error {{cannot jump}}
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else
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default: break; // expected-error {{cannot jump}}
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}
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}
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template<typename T>
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void in_switch_tmpl(int n) {
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switch (n) {
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if constexpr (sizeof(T) == 4) // expected-note 2{{constexpr if}}
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case 4: return; // expected-error {{cannot jump}}
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else
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default: break; // expected-error {{cannot jump}}
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}
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}
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void goto_scope(int n) {
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goto foo; // expected-error {{cannot jump}}
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if constexpr(sizeof(n) == 4) // expected-note {{constexpr if}}
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foo: return;
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bar:
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if constexpr(sizeof(n) == 4)
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goto bar; // ok
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}
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template<typename T>
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void goto_scope(int n) {
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goto foo; // expected-error {{cannot jump}}
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if constexpr(sizeof(n) == 4) // expected-note {{constexpr if}}
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foo: return;
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bar:
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if constexpr(sizeof(n) == 4)
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goto bar; // ok
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}
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void goto_redef(int n) {
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a: if constexpr(sizeof(n) == 4) // expected-error {{redefinition}} expected-note {{constexpr if}}
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a: goto a; // expected-note 2{{previous}}
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else
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a: goto a; // expected-error {{redefinition}} expected-error {{cannot jump}}
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}
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void evil_things() {
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goto evil_label; // expected-error {{cannot jump}}
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if constexpr (true || ({evil_label: false;})) {} // expected-note {{constexpr if}}
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if constexpr (true) // expected-note {{constexpr if}}
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goto surprise; // expected-error {{cannot jump}}
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else
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surprise: {}
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}
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}
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#endif
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