1// PR c++/54020 2// { dg-do compile { target c++11 } } 3 4// Preliminaries. 5extern int nonconst_func(int); 6constexpr int identity(int x) { return x; } 7constexpr int zero() { return identity(0); } 8constexpr int one() { return identity(1); } 9 10// Correctly accepted. 11constexpr int three = one() ? 3 : nonconst_func(0); 12 13// Incorrectly accepted. See [dcl.constexpr] #5: 14// For a constexpr function, if no function argument values exist 15// such that the function invocation sub-stitution would produce a 16// constant expression (5.19), the program is ill-formed; no diagnostic 17// required. 18constexpr int bogus() { return zero () ? 3 : nonconst_func(0); } // { dg-error "nonconst_func" } 19 20// Correctly rejected (not sure why). 21constexpr int correct_error() { return nonconst_func(0); } // { dg-error "nonconst_func" } 22 23// Correctly rejected. 24constexpr int z = bogus(); // { dg-error "" } 25 26// This is also correctly rejected. 27constexpr int correct_failure() { return 0 ? 3 : nonconst_func(0); } // { dg-error "nonconst_func" } 28