/* { dg-do compile } */ /* { dg-options "-O -Wall" } */ /* C99 6.5.2.3 Structure and union members. If the first expression has qualified type, the result has the so-qualified version of the type of the designated member. */ struct s {_Decimal32 d32; const _Decimal64 d64;}; struct sv { volatile _Decimal32 d32; volatile _Decimal64 d64; }; union u { const _Decimal64 d64; _Decimal32 d32; const struct s cs; }; struct s s; struct sv sv; const struct s cs; union u u; const union u cu; struct s g (struct s s) { return s; } union u h (union u u) { return u; } void f() { cs.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */ cs.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */ s.d64 = 1.23df; /* { dg-error "assignment of read-only member" } */ s.d32 = 1.23dd; u.d32 = 1.23dd; u.d64 = 1.23df; /* { dg-error "assignment of read-only member" } */ u.cs.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */ u.cs.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */ cu.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */ cu.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */ cu.cs.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */ cu.cs.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */ /* f().x is a valid postfix expression but is not an lvalue if function f() returning a structure or union. */ g(s).d32 = 1.23dd; /* { dg-error "lvalue required" } */ h(u).d64 = 1.23df; /* { dg-error "lvalue required" } */ /* Test assignment to volatile structure members. */ sv.d32 = 1.1df; sv.d64 = 1.1dd; }