// Test that auto-generated field constructors for unions with array
// first members compile correctly.
//
// The bug: for `union U { char data[64]; ... }`, the auto-generated
// field constructor does `__builtin_memcpy(&dst, &src, sizeof(char[64]))`.
// But `char src[64]` decays to `char *` (8 bytes) as a parameter,
// so `&src` points to the 8-byte pointer, not the 64-byte array.
//
// The field constructor cannot be called from CFA code (the resolver
// cannot match array parameters after decay), so this bug is only
// caught at compile time: with cfa_linkonce, the field constructor has
// external linkage and __attribute__((used)), forcing GCC to compile
// it and flag the bad memcpy via -Wstringop-overread.

union ArrayUnion {
	char data[64];
	long align;
};

int main() {
	ArrayUnion u;
	(void)u;
	printf( "passed\n" );
}