build/clang-plugin/tests/TestTemporaryClass.cpp

   1 #define MOZ_TEMPORARY_CLASS __attribute__((annotate("moz_temporary_class")))
   2 #define MOZ_IMPLICIT __attribute__((annotate("moz_implicit")))
   3
   4 #include <stddef.h>
   5
   6 struct MOZ_TEMPORARY_CLASS Temporary {
   7   int i;
   8   Temporary() {}
   9   MOZ_IMPLICIT Temporary(int a) {}
  10   Temporary(int a, int b) {}
  11   void *operator new(size_t x) throw() { return 0; }
  12   void *operator new(size_t blah, char *buffer) { return buffer; }
  13 };
  14
  15 template <class T>
  16 struct MOZ_TEMPORARY_CLASS TemplateClass {
  17   T i;
  18 };
  19
  20 void gobble(void *) { }
  21
  22 void gobbleref(const Temporary&) { }
  23
  24 template <class T>
  25 void gobbleanyref(const T&) { }
  26
  27 void misuseNonTemporaryClass(int len) {
  28   // All of these should error.
  29   Temporary invalid; // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated in an automatic variable}}
  30   Temporary alsoInvalid[2]; // expected-error-re {{variable of type 'Temporary{{ ?}}[2]' is only valid as a temporary}} expected-note {{value incorrectly allocated in an automatic variable}} expected-note-re {{'Temporary{{ ?}}[2]' is a temporary type because it is an array of temporary type 'Temporary'}}
  31   static Temporary invalidStatic; // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated in a global variable}}
  32   static Temporary alsoInvalidStatic[2]; // expected-error-re {{variable of type 'Temporary{{ ?}}[2]' is only valid as a temporary}} expected-note {{value incorrectly allocated in a global variable}} expected-note-re {{'Temporary{{ ?}}[2]' is a temporary type because it is an array of temporary type 'Temporary'}}
  33
  34   gobble(&invalid);
  35   gobble(&invalidStatic);
  36   gobble(&alsoInvalid[0]);
  37
  38   // All of these should be fine.
  39   gobbleref(Temporary());
  40   gobbleref(Temporary(10, 20));
  41   gobbleref(Temporary(10));
  42   gobbleref(10);
  43   gobbleanyref(TemplateClass<int>());
  44
  45   // All of these should error.
  46   gobble(new Temporary); // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated on the heap}}
  47   gobble(new Temporary[10]); // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated on the heap}}
  48   gobble(new TemplateClass<int>); // expected-error {{variable of type 'TemplateClass<int>' is only valid as a temporary}} expected-note {{value incorrectly allocated on the heap}}
  49   gobble(len <= 5 ? &invalid : new Temporary); // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated on the heap}}
  50
  51   // Placement new is odd, but okay.
  52   char buffer[sizeof(Temporary)];
  53   gobble(new (buffer) Temporary);
  54 }
  55
  56 void defaultArg(const Temporary& arg = Temporary()) { // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated in an automatic variable}}
  57 }
  58
  59 // Can't be a global, this should error.
  60 Temporary invalidStatic; // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated in a global variable}}
  61
  62 struct RandomClass {
  63   Temporary nonstaticMember; // This is okay if RandomClass is only used as a temporary.
  64   static Temporary staticMember; // expected-error {{variable of type 'Temporary' is only valid as a temporary}} expected-note {{value incorrectly allocated in a global variable}}
  65 };
  66
  67 struct BadInherit : Temporary {};
  68
  69 void useStuffWrongly() {
  70   gobbleanyref(BadInherit());
  71   gobbleanyref(RandomClass());
  72 }