/*      $NetBSD: c23.c,v 1.17 2024/11/30 11:27:20 rillig Exp $  */
# 3 "c23.c"

// Tests for the option -Ac23, which allows features from C23 and all earlier
// ISO standards, but none of the GNU extensions.
//
// See also:
//      c11.c
//      msg_353.c               for empty initializer braces

/* lint1-flags: -Ac23 -hw -X 351 */


int
bool_is_predefined_in_c23(void)
{
       bool t = true;
       bool f = false;
       return (t == true ? 20 : 0) + (f == false ? 3 : 0);
}

int
c99_bool_is_still_valid_in_c23(void)
{
       _Bool t = 1;
       _Bool f = 0;
       return (t == 1 ? 20 : 0) + (f == 0 ? 3 : 0);
}


bool
null_pointer_constant(const char *p, double dbl)
{
       /* expect+1: error: operands of '!=' have incompatible types 'double' and 'pointer to void' [107] */
       if (dbl != nullptr)
               p++;
       if (dbl > 0.0)
               p++;
       if (*p == '\0')
               p = nullptr;
       return p == nullptr;
}


void *
storage_class_in_compound_literal(void)
{
       typedef struct node node;
       struct node {
               node *left;
               int value;
               node *right;
       };

       node *tree;
       tree = &(static node){
           &(static node){
               nullptr,
               3,
               nullptr,
           },
           5,
           nullptr,
       };
       return tree->left;
}

int
empty_initializer_braces(void)
{
       struct s {
               int member;
       } s;

       // Empty initializer braces were introduced in C23.
       s = (struct s){};
       s = (struct s){s.member};
       return s.member;
}


_Static_assert(1 > 0, "string");
_Static_assert(1 > 0);


// The keyword 'thread_local' was introduced in C23.
thread_local int globally_visible;

// Thread-local functions don't make sense; lint allows them, though.
thread_local void
thread_local_function(void)
{
}

void
function(void)
{
       // Not sure whether it makes sense to have a function-scoped
       // thread-local variable.  Don't warn for now, let the compilers handle
       // this case.
       thread_local int function_scoped_thread_local;
}

// 'thread_local' can be combined with 'extern' and 'static', but with no other
// storage classes.  The other storage classes cannot be combined.
extern thread_local int extern_thread_local_1;
thread_local extern int extern_thread_local_2;
/* expect+1: warning: static variable 'static_thread_local_1' unused [226] */
static thread_local int static_thread_local_1;
/* expect+1: warning: static variable 'static_thread_local_2' unused [226] */
thread_local static int static_thread_local_2;


int
attributes(int i)
{
       // An attribute specifier list may be empty.
       [[]]i++;

       // There may be leading or trailing commas.
       [[,]]i++;

       // There may be arbitrary commas around or between the attributes.
       [[,,,,,]]i++;

       // An attribute may be a plain identifier without arguments.
       [[identifier]]i++;

       // The identifier may be prefixed with one additional identifier.
       [[prefix::identifier]]i++;

       // An attribute may have empty arguments.
       [[identifier()]]i++;

       // The arguments of an attribute may be arbitrary tokens.
       [[identifier([])]]i++;

       // The commas in this "argument list" are ordinary punctuator tokens,
       // they do not separate any arguments.
       // The structure of the attribute argument is:
       //      1. empty balanced token sequence between '[' and ']'
       //      2. token ','
       //      3. empty balanced token sequence between '{' and '}'
       //      4. token ','
       //      5. empty balanced token sequence between '(' and ')'
       [[identifier([], {}, ())]]i++;

       // Inside an argument, parentheses may be nested.
       [[identifier(((((())))))]]i++;
       // Inside an argument, brackets may be nested.
       [[identifier([[[[[]]]]])]]i++;
       // Inside an argument, braces may be nested.
       [[identifier({{{{{}}}}})]]i++;

       // An attribute argument may contain arbitrary punctuation.
       [[identifier(++++ ? ? ? : : :: )]]i++;

       // An attribute argument may contain constants and string literals.
       [[identifier(0, 0.0, "hello" " " "world")]]i++;

       // There may be multiple attribute specifier sequences in a row.
       [[]][[]][[]]i++;

       // An attribute may occur more than once.
       [[
               maybe_unused, maybe_unused, maybe_unused, maybe_unused,
               maybe_unused, maybe_unused, maybe_unused, maybe_unused,
               maybe_unused, maybe_unused, maybe_unused, maybe_unused,
               maybe_unused, maybe_unused, maybe_unused, maybe_unused,
               maybe_unused, maybe_unused, maybe_unused, maybe_unused,
       ]]i++;

       return i;
}

typedef int number;

void
attributes_in_parameter_declaration(
   [[maybe_unused]] int int_param,
   [[maybe_unused]] const int const_int_param,
   [[maybe_unused]] number typedef_param,
   [[maybe_unused]] const number const_typedef_param)
{
}

int
attribute_in_switch_statement(int n)
{
       switch (n) {
       case 1:
               n++;
       /* expect+1: warning: fallthrough on case statement [220] */
       case 2:
               n++;
               [[fallthrough]];
       case 3:
               n++;
               [[fallthrough]];
       default:
               n++;
       }
       return n;
}