1 // { dg-do compile { target c++11 } }
2 
3 // From N2235
4 
5 // Mess with the builtin by redeclaring.
abs(int x)6 constexpr int abs(int x) { return x < 0 ? -x : x; }
7 
8 extern "C"
9 {
10   constexpr float
squaref(float x)11   squaref(float x) { return x * x; }
12 }
13 
14 // implicitly inline, already: warn?
15 inline constexpr double
squared(double x)16 squared(double x) { return x * x; }
17 
squarei(int x)18 constexpr int squarei(int x) { return x * x; }
19 extern const int side; // { dg-message "not initialized with a constant expression" }
20 constexpr int area = squarei(side); // { dg-error "side|argument" }
21 // error: squarei(side) is not a constant expression
22 
next(constexpr int x)23 int next(constexpr int x) // { dg-error "parameter" }
24 { return x + 1; }
25 
f(int x)26 constexpr void f(int x)       // { dg-error "return type .void" "" { target c++11_only } }
27 { /* ... */ }
28 
prev(int x)29 constexpr int prev(int x)
30 { return --x; }               // { dg-error "--" "" { target c++11_only } }
31 
g(int x,int n)32 constexpr int g(int x, int n) // error: body not just ‘‘return expr’’
33 {
34    int r = 1;
35    while (--n > 0) r *= x;
36    return r;
37 } // { dg-error "not a return-statement" "" { target c++11_only } }
38 
39 constexpr int
bar(int x,int y)40 bar(int x, int y) { return x + y + x * y; } // { dg-message "previously" }
41 
bar(int x,int y)42 int bar(int x, int y)	     // { dg-error "redefinition" }
43 { return x * 2 + 3 * y; }
44 
45 constexpr int twice(int x);  // { dg-message "never defined" }
46 enum { bufsz = twice(256) }; // { dg-error "" } twice() isn’t (yet) defined
47 
fac(int x)48 constexpr int fac(int x)
49 { return x > 2 ? x * fac(x - 1) : 1; } // OK
50