// RUN: %clang_cc1 -fsyntax-only -verify=cxx11 -std=c++11 -Wno-unused -Wno-uninitialized \
// RUN: -Wunsequenced -Wno-c++17-extensions -Wno-c++14-extensions %s
// RUN: %clang_cc1 -fsyntax-only -verify=cxx17 -std=c++17 -Wno-unused -Wno-uninitialized \
// RUN: -Wunsequenced -Wno-c++17-extensions -Wno-c++14-extensions %s
int f(int, int = 0);
int g1();
int g2(int);
struct A {
int x, y;
};
struct S {
S(int, int);
int n;
};
void test() {
int a;
int xs[10];
++a = 0; // ok
a + ++a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
a = ++a; // ok
a + a++; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
a = a++; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
++ ++a; // ok
(a++, a++); // ok
++a + ++a; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
a++ + a++; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
(a++, a) = 0; // ok, increment is sequenced before value computation of LHS
a = xs[++a]; // ok
a = xs[a++]; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
(a ? xs[0] : xs[1]) = ++a; // cxx11-warning {{unsequenced modification and access to 'a'}}
a = (++a, ++a); // ok
a = (a++, ++a); // ok
a = (a++, a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
f(a, a); // ok
f(a = 0, a); // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
f(a, a += 0); // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
f(a = 0, a = 0); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
a = f(++a); // ok
a = f(a++); // ok
a = f(++a, a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
// Compound assignment "A OP= B" is equivalent to "A = A OP B" except that A
// is evaluated only once.
(++a, a) = 1; // ok
(++a, a) += 1; // ok
a = ++a; // ok
a += ++a; // cxx11-warning {{unsequenced modification and access to 'a'}}
A agg1 = { a++, a++ }; // ok
A agg2 = { a++ + a, a++ }; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
S str1(a++, a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
S str2 = { a++, a++ }; // ok
S str3 = { a++ + a, a++ }; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
struct Z { A a; S s; } z = { { ++a, ++a }, { ++a, ++a } }; // ok
a = S { ++a, a++ }.n; // ok
A { ++a, a++ }.x; // ok
a = A { ++a, a++ }.x; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
A { ++a, a++ }.x + A { ++a, a++ }.y; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
(xs[2] && (a = 0)) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(0 && (a = 0)) + a; // ok
(1 && (a = 0)) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(xs[3] || (a = 0)) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(0 || (a = 0)) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(1 || (a = 0)) + a; // ok
(xs[4] ? a : ++a) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(0 ? a : ++a) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(1 ? a : ++a) + a; // ok
(0 ? a : a++) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(1 ? a : a++) + a; // ok
(xs[5] ? ++a : ++a) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
(++a, xs[6] ? ++a : 0) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
// Here, the read of the fourth 'a' might happen before or after the write to
// the second 'a'.
a += (a++, a) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
a = a++ && a; // ok
A *q = &agg1;
(q = &agg2)->y = q->x; // cxx11-warning {{unsequenced modification and access to 'q'}}
// This has undefined behavior if a == 0; otherwise, the side-effect of the
// increment is sequenced before the value computation of 'f(a, a)', which is
// sequenced before the value computation of the '&&', which is sequenced
// before the assignment. We treat the sequencing in '&&' as being
// unconditional.
a = a++ && f(a, a);
// This has undefined behavior if a != 0.
(a && a++) + a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
// FIXME: Don't warn here.
(xs[7] && ++a) * (!xs[7] && ++a); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
xs[0] = (a = 1, a); // ok
(a -= 128) &= 128; // ok
++a += 1; // ok
xs[8] ? ++a + a++ : 0; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
xs[8] ? 0 : ++a + a++; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
xs[8] ? ++a : a++; // no-warning
xs[8] ? a+=1 : a+= 2; // no-warning
(xs[8] ? a+=1 : a+= 2) = a; // cxx11-warning {{unsequenced modification and access to 'a'}}
(xs[8] ? a+=1 : a) = a; // cxx11-warning {{unsequenced modification and access to 'a'}}
(xs[8] ? a : a+= 2) = a; // cxx11-warning {{unsequenced modification and access to 'a'}}
a = (xs[8] ? a+=1 : a+= 2); // no-warning
a += (xs[8] ? a+=1 : a+= 2); // cxx11-warning {{unsequenced modification and access to 'a'}}
(false ? a+=1 : a) = a; // no-warning
(true ? a+=1 : a) = a; // cxx11-warning {{unsequenced modification and access to 'a'}}
(false ? a : a+=2) = a; // cxx11-warning {{unsequenced modification and access to 'a'}}
(true ? a : a+=2) = a; // no-warning
xs[8] && (++a + a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
xs[8] || (++a + a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
((a++, false) || (a++, false)); // no-warning PR39779
((a++, true) && (a++, true)); // no-warning PR39779
int i,j;
(i = g1(), false) || (j = g2(i)); // no-warning PR22197
(i = g1(), true) && (j = g2(i)); // no-warning PR22197
(a++, false) || (a++, false) || (a++, false) || (a++, false); // no-warning
(a++, true) || (a++, true) || (a++, true) || (a++, true); // no-warning
a = ((a++, false) || (a++, false) || (a++, false) || (a++, false)); // no-warning
a = ((a++, true) && (a++, true) && (a++, true) && (a++, true)); // no-warning
a = ((a++, false) || (a++, false) || (a++, false) || a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
a = ((a++, true) && (a++, true) && (a++, true) && a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
a = ((a++, false) || (a++, false) || (a++, false) || (a + a, false)); // no-warning
a = ((a++, true) && (a++, true) && (a++, true) && (a + a, true)); // no-warning
a = (false && a++); // no-warning
a = (true && a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
a = (true && ++a); // no-warning
a = (true || a++); // no-warning
a = (false || a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
a = (false || ++a); // no-warning
(a++) | (a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
(a++) & (a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
(a++) ^ (a++); // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
(__builtin_classify_type(++a) ? 1 : 0) + ++a; // ok
(__builtin_constant_p(++a) ? 1 : 0) + ++a; // ok
(__builtin_object_size(&(++a, a), 0) ? 1 : 0) + ++a; // ok
(__builtin_expect(++a, 0) ? 1 : 0) + ++a; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
int *p = xs;
a = *(a++, p); // no-warning
p[(long long unsigned)(p = 0)]; // cxx11-warning {{unsequenced modification and access to 'p'}}
(i++, xs)[i++]; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
(++i, xs)[++i]; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
(i, xs)[++i + ++i]; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'i'}}
p++[p == xs]; // cxx11-warning {{unsequenced modification and access to 'p'}}
++p[p++ == xs]; // cxx11-warning {{unsequenced modification and access to 'p'}}
struct S { int x; } s, *ps = &s;
int (S::*PtrMem);
(PtrMem = &S::x ,s).*(PtrMem); // cxx11-warning {{unsequenced modification and access to 'PtrMem'}}
(PtrMem = &S::x ,s).*(PtrMem = &S::x); // cxx11-warning {{multiple unsequenced modifications to 'PtrMem'}}
(PtrMem = &S::x ,ps)->*(PtrMem); // cxx11-warning {{unsequenced modification and access to 'PtrMem'}}
(PtrMem = &S::x ,ps)->*(PtrMem = &S::x); // cxx11-warning {{multiple unsequenced modifications to 'PtrMem'}}
(PtrMem = nullptr) == (PtrMem = nullptr); // cxx11-warning {{multiple unsequenced modifications to 'PtrMem'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'PtrMem'}}
(PtrMem = nullptr) == PtrMem; // cxx11-warning {{unsequenced modification and access to 'PtrMem'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'PtrMem'}}
i++ << i++; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
++i << ++i; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
i++ << i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i << i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i++ >> i++; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
++i >> ++i; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
i++ >> i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i >> i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
(i++ << i) + i; // cxx11-warning {{unsequenced modification and access to 'i'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'i'}}
(i++ << i) << i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
++i = i++; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
i = i+= 1; // no-warning
i = i++ + ++i; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'i'}}
++i += ++i; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
++i += i++; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
(i++, i) += ++i; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
(i++, i) += i++; // cxx11-warning {{multiple unsequenced modifications to 'i'}}
i += i+= 1; // cxx11-warning {{unsequenced modification and access to 'i'}}
i += i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i += ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i -= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i -= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i *= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i *= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i /= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i /= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i %= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i %= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i ^= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i ^= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i |= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i |= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i &= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i &= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i <<= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i <<= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
i >>= i++; // cxx11-warning {{unsequenced modification and access to 'i'}}
i >>= ++i; // cxx11-warning {{unsequenced modification and access to 'i'}}
p[i++] = i; // cxx11-warning {{unsequenced modification and access to 'i'}}
p[i++] = (i = 42); // cxx11-warning {{multiple unsequenced modifications to 'i'}}
p++[i++] = (i = p ? i++ : i++); // cxx11-warning {{unsequenced modification and access to 'p'}}
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
(i++, f)(i++, 42); // cxx11-warning {{multiple unsequenced modifications to 'i'}}
(i++ + i++, f)(42, 42); // cxx11-warning {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'i'}}
int (*pf)(int, int);
(pf = f)(pf != nullptr, pf != nullptr); // cxx11-warning {{unsequenced modification and access to 'pf'}}
pf((pf = f) != nullptr, 42); // cxx11-warning {{unsequenced modification and access to 'pf'}}
f((pf = f, 42), (pf = f, 42)); // cxx11-warning {{multiple unsequenced modifications to 'pf'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'pf'}}
pf((pf = f) != nullptr, pf == nullptr); // cxx11-warning {{unsequenced modification and access to 'pf'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'pf'}}
}
namespace PR20819 {
struct foo { void bar(int); };
foo get_foo(int);
void g() {
int a = 0;
get_foo(a).bar(a++); // cxx11-warning {{unsequenced modification and access to 'a'}}
}
}
namespace overloaded_operators {
struct E {
E &operator=(E &);
E operator()(E);
E operator()(E, E);
E operator[](E);
} e;
// Binary operators with unsequenced operands.
E operator+(E,E);
E operator-(E,E);
E operator*(E,E);
E operator/(E,E);
E operator%(E,E);
E operator^(E,E);
E operator&(E,E);
E operator|(E,E);
E operator<(E,E);
E operator>(E,E);
E operator==(E,E);
E operator!=(E,E);
E operator>=(E,E);
E operator<=(E,E);
// Binary operators where the RHS is sequenced before the LHS in C++17.
E operator+=(E,E);
E operator-=(E,E);
E operator*=(E,E);
E operator/=(E,E);
E operator%=(E,E);
E operator^=(E,E);
E operator&=(E,E);
E operator|=(E,E);
E operator<<=(E,E);
E operator>>=(E,E);
// Binary operators where the LHS is sequenced before the RHS in C++17.
E operator<<(E,E);
E operator>>(E,E);
E operator&&(E,E);
E operator||(E,E);
E operator,(E,E);
E operator->*(E,E);
void test() {
int i = 0;
// Binary operators with unsequenced operands.
((void)i++,e) + ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) - ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) * ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) / ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) % ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) ^ ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) & ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) | ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) < ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) > ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) == ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) != ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) <= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) >= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
// Binary operators where the RHS is sequenced before the LHS in C++17.
((void)i++,e) = ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) += ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) -= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) *= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) /= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) %= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) ^= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) &= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) |= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) <<= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) >>= ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
operator+=(((void)i++,e), ((void)i++,e));
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
// Binary operators where the LHS is sequenced before the RHS in C++17.
((void)i++,e) << ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) >> ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) || ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) && ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e) , ((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e)->*((void)i++,e);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
operator<<(((void)i++,e), ((void)i++,e));
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e)[((void)i++,e)];
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
((void)i++,e)(((void)i++,e));
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
e(((void)i++,e), ((void)i++,e));
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
((void)i++,e).operator()(((void)i++,e));
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
}
}
namespace PR35340 {
struct S {};
S &operator<<(S &, int);
void test() {
S s;
int i = 0;
s << i++ << i++;
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
operator<<(operator<<(s, i++), i++);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'i'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'i'}}
}
}
namespace members {
struct S1 {
unsigned bf1 : 2;
unsigned bf2 : 2;
unsigned a;
unsigned b;
static unsigned x;
void member_f(S1 &s);
};
void S1::member_f(S1 &s) {
++a + ++a; // cxx11-warning {{multiple unsequenced modifications to 'a'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'a'}}
a + ++a; // cxx11-warning {{unsequenced modification and access to 'a'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'a'}}
++a + ++b; // no-warning
a + ++b; // no-warning
// TODO: Warn here.
++s.a + ++s.a; // no-warning TODO {{multiple unsequenced modifications to}}
s.a + ++s.a; // no-warning TODO {{unsequenced modification and access to}}
++s.a + ++s.b; // no-warning
s.a + ++s.b; // no-warning
++a + ++s.a; // no-warning
a + ++s.a; // no-warning
++a + ++s.b; // no-warning
a + ++s.b; // no-warning
// TODO Warn here for bit-fields in the same memory location.
++bf1 + ++bf1; // cxx11-warning {{multiple unsequenced modifications to 'bf1'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'bf1'}}
bf1 + ++bf1; // cxx11-warning {{unsequenced modification and access to 'bf1'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'bf1'}}
++bf1 + ++bf2; // no-warning TODO {{multiple unsequenced modifications to}}
bf1 + ++bf2; // no-warning TODO {{unsequenced modification and access to}}
// TODO Warn here for bit-fields in the same memory location.
++s.bf1 + ++s.bf1; // no-warning TODO {{multiple unsequenced modifications to}}
s.bf1 + ++s.bf1; // no-warning TODO {{unsequenced modification and access to}}
++s.bf1 + ++s.bf2; // no-warning TODO {{multiple unsequenced modifications to}}
s.bf1 + ++s.bf2; // no-warning TODO {{unsequenced modification and access to}}
++bf1 + ++s.bf1; // no-warning
bf1 + ++s.bf1; // no-warning
++bf1 + ++s.bf2; // no-warning
bf1 + ++s.bf2; // no-warning
struct Der : S1 {};
Der d;
Der &d_ref = d;
S1 &s1_ref = d_ref;
++s1_ref.a + ++d_ref.a; // no-warning TODO {{multiple unsequenced modifications to member 'a' of 'd'}}
++s1_ref.a + d_ref.a; // no-warning TODO {{unsequenced modification and access to member 'a' of 'd'}}
++s1_ref.a + ++d_ref.b; // no-warning
++s1_ref.a + d_ref.b; // no-warning
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++s.x + x; // no-warning TODO {{unsequenced modification and access to static member 'x' of 'S1'}}
++this->x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++d_ref.x + ++S1::x; // no-warning TODO {{unsequenced modification and access to static member 'x' of 'S1'}}
}
struct S2 {
union { unsigned x, y; };
void f2();
};
void S2::f2() {
++x + ++x; // no-warning TODO {{multiple unsequenced modifications to}}
x + ++x; // no-warning TODO {{unsequenced modification and access to}}
++x + ++y; // no-warning
x + ++y; // no-warning
}
void f2(S2 &s) {
++s.x + ++s.x; // no-warning TODO {{multiple unsequenced modifications to}}
s.x + ++s.x; // no-warning TODO {{unsequenced modification and access to}}
++s.x + ++s.y; // no-warning
s.x + ++s.y; // no-warning
}
struct S3 {
union {
union {
unsigned x;
};
};
unsigned y;
void f3();
};
void S3::f3() {
++x + ++x; // no-warning TODO {{multiple unsequenced modifications to}}
x + ++x; // no-warning TODO {{unsequenced modification and access to}}
++x + ++y; // no-warning
x + ++y; // no-warning
}
void f3(S3 &s) {
++s.x + ++s.x; // no-warning TODO {{multiple unsequenced modifications to}}
s.x + ++s.x; // no-warning TODO {{unsequenced modification and access to}}
++s.x + ++s.y; // no-warning
s.x + ++s.y; // no-warning
}
struct S4 : S3 {
unsigned y;
void f4();
};
void S4::f4() {
++x + ++x; // no-warning TODO {{multiple unsequenced modifications to}}
x + ++x; // no-warning TODO {{unsequenced modification and access to}}
++x + ++y; // no-warning
x + ++y; // no-warning
++S3::y + ++y; // no-warning
S3::y + ++y; // no-warning
}
void f4(S4 &s) {
++s.x + ++s.x; // no-warning TODO {{multiple unsequenced modifications to}}
s.x + ++s.x; // no-warning TODO {{unsequenced modification and access to}}
++s.x + ++s.y; // no-warning
s.x + ++s.y; // no-warning
++s.S3::y + ++s.y; // no-warning
s.S3::y + ++s.y; // no-warning
}
static union {
unsigned Ux;
unsigned Uy;
};
void f5() {
++Ux + ++Ux; // no-warning TODO {{multiple unsequenced modifications to}}
Ux + ++Ux; // no-warning TODO {{unsequenced modification and access to}}
++Ux + ++Uy; // no-warning
Ux + ++Uy; // no-warning
}
void f6() {
struct S { unsigned x, y; } s;
++s.x + ++s.x; // no-warning TODO {{multiple unsequenced modifications to}}
s.x + ++s.x; // no-warning TODO {{unsequenced modification and access to}}
++s.x + ++s.y; // no-warning
s.x + ++s.y; // no-warning
struct { unsigned x, y; } t;
++t.x + ++t.x; // no-warning TODO {{multiple unsequenced modifications to}}
t.x + ++t.x; // no-warning TODO {{unsequenced modification and access to}}
++t.x + ++t.y; // no-warning
t.x + ++t.y; // no-warning
}
} // namespace members
namespace references {
void reference_f() {
// TODO: Check that we can see through references.
// For now this is completely unhandled.
int a;
int xs[10];
int &b = a;
int &c = b;
int &ra1 = c;
int &ra2 = b;
int other;
++ra1 + ++ra2; // no-warning TODO {{multiple unsequenced modifications to}}
ra1 + ++ra2; // no-warning TODO {{unsequenced modification and access to}}
++ra1 + ++other; // no-warning
ra1 + ++other; // no-warning
// Make sure we handle reference cycles.
int &ref_cycle = ref_cycle;
++ref_cycle + ++ref_cycle; // cxx11-warning {{multiple unsequenced modifications to 'ref_cycle'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'ref_cycle'}}
ref_cycle + ++ref_cycle; // cxx11-warning {{unsequenced modification and access to 'ref_cycle'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'ref_cycle'}}
}
} // namespace references
namespace std {
using size_t = decltype(sizeof(0));
template<typename> struct tuple_size;
template<size_t, typename> struct tuple_element { using type = int; };
}
namespace bindings {
struct A { int x, y; };
typedef int B[2];
struct C { template<int> int get(); };
struct D : A {};
} // namespace bindings
template<> struct std::tuple_size<bindings::C> { enum { value = 2 }; };
namespace bindings {
void testa() {
A a;
{
auto [x, y] = a;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
++x + ++a.x; // no-warning
++x + a.x; // no-warning
}
{
auto &[x, y] = a;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
++x + ++a.x; // no-warning TODO
++x + a.x; // no-warning TODO
}
}
void testb() {
B b;
{
auto [x, y] = b;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
++x + ++b[0]; // no-warning
++x + b[0]; // no-warning
}
{
auto &[x, y] = b;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
++x + ++b[0]; // no-warning TODO
++x + b[0]; // no-warning TODO
}
}
void testc() {
C c;
{
auto [x, y] = c;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
}
{
auto &[x, y] = c;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
}
}
void testd() {
D d;
{
auto [x, y] = d;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
++x + ++d.x; // no-warning
++x + d.x; // no-warning
}
{
auto &[x, y] = d;
++x + ++x; // cxx11-warning {{multiple unsequenced modifications to 'x'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'x'}}
++x + x; // cxx11-warning {{unsequenced modification and access to 'x'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'x'}}
++x + ++y; // no-warning
++x + y; // no-warning
++x + ++d.x; // no-warning TODO
++x + d.x; // no-warning TODO
}
}
} // namespace bindings
namespace templates {
template <typename T>
struct Bar {
T get() { return 0; }
};
template <typename X>
struct Foo {
int Run();
Bar<int> bar;
};
enum E {e1, e2};
bool operator&&(E, E);
void foo(int, int);
template <typename X>
int Foo<X>::Run() {
char num = 0;
// Before instantiation, Clang may consider the builtin operator here as
// unresolved function calls, and treat the arguments as unordered when
// the builtin operator evaluatation is well-ordered. Waiting until
// instantiation to check these expressions will prevent false positives.
if ((num = bar.get()) < 5 && num < 10) { }
if ((num = bar.get()) < 5 || num < 10) { }
if (static_cast<E>((num = bar.get()) < 5) || static_cast<E>(num < 10)) { }
if (static_cast<E>((num = bar.get()) < 5) && static_cast<E>(num < 10)) { }
// cxx11-warning@-1 {{unsequenced modification and access to 'num'}}
foo(num++, num++);
// cxx11-warning@-1 {{multiple unsequenced modifications to 'num'}}
// cxx17-warning@-2 {{multiple unsequenced modifications to 'num'}}
return 1;
}
int x = Foo<int>().Run();
// cxx11-note@-1 {{in instantiation of member function 'templates::Foo<int>::Run'}}
// cxx17-note@-2 {{in instantiation of member function 'templates::Foo<int>::Run'}}
template <typename T>
int Run2() {
T t = static_cast<T>(0);
return (t = static_cast<T>(1)) && t;
// cxx11-warning@-1 {{unsequenced modification and access to 't'}}
}
int y = Run2<bool>();
int z = Run2<E>();
// cxx11-note@-1{{in instantiation of function template specialization 'templates::Run2<templates::E>' requested here}}
template <typename T> int var = sizeof(T);
void test_var() {
var<int>++ + var<int>++; // cxx11-warning {{multiple unsequenced modifications to 'var<int>'}}
// cxx17-warning@-1 {{multiple unsequenced modifications to 'var<int>'}}
var<int>++ + var<int>; // cxx11-warning {{unsequenced modification and access to 'var<int>'}}
// cxx17-warning@-1 {{unsequenced modification and access to 'var<int>'}}
int &r = var<int>;
r++ + var<int>++; // no-warning TODO {{multiple unsequenced modifications to 'var<int>'}}
r++ + var<long>++; // no-warning
}
} // namespace templates
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