gcc/testsuite/gcc.dg/dfp/struct-union.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O -Wall" } */
   3
   4 /* C99 6.5.2.3 Structure and union members.
   5    If the first expression has qualified type, the result has the so-qualified
   6    version of the type of the designated member.  */
   7
   8 struct s {_Decimal32 d32; const _Decimal64 d64;};
   9 struct sv { volatile _Decimal32 d32; volatile _Decimal64 d64; };
  10 union u
  11 {
  12   const _Decimal64 d64;
  13   _Decimal32 d32;
  14   const struct s cs;
  15 };
  16
  17 struct s s;
  18 struct sv sv;
  19 const struct s cs;
  20
  21 union u u;
  22 const union u cu;
  23
  24 struct s g (struct s s)
  25 {
  26   return s;
  27 }
  28
  29 union u h (union u u)
  30 {
  31   return u;
  32 }
  33
  34 void f()
  35 {
  36   cs.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */
  37   cs.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */
  38   s.d64 = 1.23df;  /* { dg-error "assignment of read-only member" } */
  39
  40   s.d32 = 1.23dd;
  41   u.d32 = 1.23dd;
  42
  43   u.d64 = 1.23df;    /* { dg-error "assignment of read-only member" } */
  44   u.cs.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */
  45   u.cs.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */
  46
  47   cu.d32 = 1.23dd;   /* { dg-error "assignment of member 'd32' in read-only object" } */
  48
  49   cu.d64 = 1.23df;    /* { dg-error "assignment of member 'd64' in read-only object" } */
  50   cu.cs.d32 = 1.23dd; /* { dg-error "assignment of member 'd32' in read-only object" } */
  51   cu.cs.d64 = 1.23df; /* { dg-error "assignment of member 'd64' in read-only object" } */
  52
  53   /* f().x is a valid postfix expression but is not an lvalue if
  54      function f() returning a structure or union.  */
  55   g(s).d32 = 1.23dd;  /* { dg-error "lvalue required" } */
  56   h(u).d64 = 1.23df;  /* { dg-error "lvalue required" } */
  57
  58   /* Test assignment to volatile structure members.  */
  59   sv.d32 = 1.1df;
  60   sv.d64 = 1.1dd;
  61 }
  62