/* PR c++/90938 - Initializing array with {1} works, but not {0} { dg-do compile { target c++11 } } { dg-options "-O -Wall -fdump-tree-optimized" } */ #define assert(e) \ ((e) ? (void)0 \ : (__builtin_printf ("assertion failed on line %i: %s\n", \ __LINE__, #e), \ __builtin_abort ())) namespace A { struct X { X () = default; X (int n) : n (n + 1) { } int n; }; static_assert (__is_trivial (X), "X is trivial"); static void test () { { X x[] { 0 }; assert (1 == x->n); } { X x[1] { 0 }; assert (1 == x->n); // fails } { X x[2] { 0 }; assert (1 == x[0].n && 0 == x[1].n); // fails } { X x[] { 1, 0 }; assert (2 == x[0].n && 1 == x[1].n); // passes } { X x[2] { 1, 0 }; assert (2 == x[0].n && 1 == x[1].n); // fails } } } namespace B { struct X { X () = default; X (int *p) : p (p ? p : new int (1)) { } int *p; }; static_assert (__is_trivial (X), "X is trivial"); static void test () { X x[1] { nullptr }; assert (*x->p == 1); // fails X y[1] { 0 }; assert (*y->p == 1); // fails } } namespace C { static const char *vector_swizzle (int vecsize, int index) { static const char *swizzle[4][4] = { { ".x", ".y", ".z", ".w" }, { ".xy", ".yz", ".zw", nullptr }, { ".xyz", ".yzw", nullptr, nullptr }, { "", nullptr, nullptr, nullptr }, }; assert (vecsize >= 1 && vecsize <= 4); assert (index >= 0 && index < 4); assert (swizzle[vecsize - 1][index]); return swizzle[vecsize - 1][index]; } static void test () { assert (!*vector_swizzle(4, 0)); } } int main () { A::test (); B::test (); C::test (); } // { dg-final { scan-tree-dump-not "abort" "optimized" } }