gcc/testsuite/gcc.dg/c23-auto-3.c

   1 /* Test C23 auto.  Invalid code.  */
   2 /* { dg-do compile } */
   3 /* { dg-options "-std=c23 -pedantic-errors" } */
   4
   5 auto; /* { dg-error "empty declaration" } */
   6 auto *p = (int *) 0; /* { dg-error "plain identifier" } */
   7 auto i; /* { dg-error "initialized data declaration" } */
   8 auto g { } /* { dg-error "initialized data declaration" } */
   9 auto a = 1, b = 2; /* { dg-error "single declarator" } */
  10 auto long e0 = 0; /* { dg-error "file-scope declaration" } */
  11 long auto e1 = 0; /* { dg-error "file-scope declaration" } */
  12 int auto e2 = 0; /* { dg-error "file-scope declaration" } */
  13
  14 extern int e3;
  15 auto e3 = 1; /* { dg-error "underspecified declaration of 'e3', which is already declared in this scope" } */
  16
  17 void
  18 f ()
  19 {
  20   extern int fe1;
  21   auto fe1 = 1; /* { dg-error "underspecified declaration of 'fe1', which is already declared in this scope" } */
  22   /* { dg-error "declaration of 'fe1' with no linkage follows extern declaration" "linkage error" { target *-*-* } .-1 } */
  23   auto fe2 = (struct s *) 0; /* { dg-error "declared in underspecified object initializer" } */
  24   auto fe3 = (union u *) 0; /* { dg-error "declared in underspecified object initializer" } */
  25   auto fe4 = (struct s2 { int a; }) { }; /* { dg-error "defined in underspecified object initializer" } */
  26   auto fe5 = (struct { int a; }) { }; /* { dg-error "defined in underspecified object initializer" } */
  27   auto fe6 = (union u2 { int a; }) { }; /* { dg-error "defined in underspecified object initializer" } */
  28   auto fe7 = (union { int a; }) { }; /* { dg-error "defined in underspecified object initializer" } */
  29   auto fe8 = sizeof (enum e { A }); /* { dg-error "defined in underspecified object initializer" } */
  30   /* The following case is undefined behavior (so doesn't actually require a
  31      diagnostic).  */
  32   auto fe9 = sizeof (enum { B }); /* { dg-error "defined in underspecified object initializer" } */
  33   /* Examples with a forward declaration, then definition inside auto.  */
  34   struct s3;
  35   auto fe10 = (struct s3 { int a; }) { }; /* { dg-error "defined in underspecified object initializer" } */
  36   union u3;
  37   auto fe11 = (union u3 { int a; }) { }; /* { dg-error "defined in underspecified object initializer" } */
  38 }
  39
  40 void f2 (auto x); /* { dg-error "storage class specified for parameter" } */
  41 void f3 (auto y) { } /* { dg-error "storage class specified for parameter" } */
  42
  43 auto e4 = sizeof (e4); /* { dg-error "underspecified 'e4' referenced in its initializer" } */
  44 __SIZE_TYPE__ e5;
  45 void
  46 f4 ()
  47 {
  48   auto e5 = sizeof (e5); /* { dg-error "underspecified 'e5' referenced in its initializer" } */
  49 }
  50
  51 auto typedef int T; /* { dg-error "'typedef' used with 'auto'" } */
  52 auto auto e6 = 1; /* { dg-error "duplicate 'auto'" } */
  53 static auto int e7 = 1; /* { dg-error "multiple storage classes in declaration specifiers" } */
  54 _Thread_local auto int e8 = 2; /* { dg-error "'_Thread_local' used with 'auto'" } */
  55 _Thread_local int auto e9 = 3; /* { dg-error "'_Thread_local' used with 'auto'" } */
  56 /* { dg-error "file-scope declaration of 'e9' specifies 'auto'" "file-scope error" { target *-*-* } .-1 } */
  57
  58 typedef auto int T2; /* { dg-error "multiple storage classes in declaration specifiers" } */
  59
  60 void
  61 f5 ()
  62 {
  63   static int auto e10 = 3; /* { dg-error "multiple storage classes in declaration specifiers" } */
  64 }
  65
  66 void
  67 f6 ()
  68 {
  69   static auto l = { 0L }; /* { dg-error "expected expression" } */
  70   const auto i3 [[]] = { 4, }; /* { dg-error "expected expression" } */
  71 }