gcc/testsuite/gdc.test/compilable/noreturn1.d

   1 /*
   2 REQUIRED_ARGS: -w
   3 TEST_OUTPUT:
   4 ---
   5 noreturn
   6 ---
   7
   8 Basic properties and usage mentioned in the DIP:
   9 https://github.com/dlang/DIPs/blob/master/DIPs/accepted/DIP1034.md
  10 */
  11
  12 alias noreturn = typeof(*null);
  13 pragma(msg, noreturn);
  14
  15 static assert(!is(noreturn == void));
  16
  17 // Fails
  18 // static assert(is( typeof([]) == noreturn[] ));
  19 // static assert(is( typeof([][0]) == noreturn ));
  20
  21 static assert(is( typeof(assert(0)) == noreturn ));
  22
  23 // Does not parse yet
  24 // static assert(is( typeof(throw new Exception()) == noreturn ));
  25
  26 static assert(is(noreturn == noreturn));
  27 static assert(!is(noreturn == const noreturn));
  28 static assert(is(noreturn : const noreturn));
  29
  30 static assert(!is(noreturn == int));
  31 static assert(is(noreturn : int));
  32
  33 // Covariance
  34 static assert(is(noreturn[] : int[]));
  35 static assert(is(noreturn* : int*));
  36 static assert(is(noreturn function() : int function()));
  37 static assert(is(noreturn delegate() : int delegate()));
  38
  39 // Reject inverse conversions
  40 static assert(!is(int[]          : noreturn[]));
  41 static assert(!is(int*           : noreturn*));
  42 static assert(!is(int function() : noreturn function()));
  43 static assert(!is(int delegate() : noreturn delegate()));
  44
  45 static assert(noreturn.mangleof == "Nn"); // Changed from b due to conflicts with bool
  46 static assert(noreturn.sizeof == 0);
  47 static assert(noreturn.alignof == 0);
  48
  49 static assert((noreturn*).sizeof == (int*).sizeof);
  50 static assert((noreturn[]).sizeof == (int[]).sizeof);
  51
  52 static assert(is(typeof(noreturn.init) == noreturn));
  53 static assert(is(typeof((const noreturn).init) == const noreturn));
  54 static assert(is(typeof((immutable noreturn).init) == immutable noreturn));
  55 static assert(is(typeof((shared noreturn).init) == shared noreturn));
  56
  57 version (DigitalMars)
  58     noreturn exits(int* p)
  59     {
  60         *p = 3;
  61         assert(false); // *p could be valid
  62     }
  63
  64 noreturn exit();
  65
  66 noreturn pureexits() @nogc nothrow pure @safe { assert(0); }
  67
  68 noreturn callpureexits() { pureexits(); }
  69
  70 noreturn returnExits()
  71 {
  72     return pureexits();
  73 }
  74
  75 void alsoExits()
  76 {
  77     return assert(0);
  78 }
  79
  80 int thisAlsoExits()
  81 {
  82     return assert(0);
  83 }
  84
  85 void cast_()
  86 {
  87     noreturn n;
  88     int i = n;
  89 }
  90
  91 int test1(int i)
  92 {
  93     if (exit())
  94         return i + 1;
  95     return i - 1;
  96 }
  97
  98 noreturn tlsNoreturn;
  99 __gshared noreturn globalNoreturn;
 100
 101 template CreateTLS(A)
 102 {
 103     A a;
 104 }
 105
 106 void* useTls()
 107 {
 108     alias Tnr = CreateTLS!noreturn;
 109     void* a1 = &Tnr.a;
 110     void* a2 = &tlsNoreturn;
 111     void* a3 = &globalNoreturn;
 112     return a1 < a2 ? a2 : a3;
 113 }