clang/test/Sema/block-return.c

   1 // RUN: %clang_cc1 -Wno-int-to-pointer-cast -Wno-pointer-to-int-cast -pedantic -fsyntax-only %s -verify -fblocks
   2
   3 typedef void (^CL)(void);
   4
   5 CL foo(void) {
   6   short y;
   7   short (^add1)(void) = ^{ return y+1; }; // expected-error {{incompatible block pointer types initializing 'short (^)(void)' with an expression of type 'int (^)(void)'}}
   8
   9   CL X = ^{
  10     if (2)
  11       return;
  12     return 1;  // expected-error {{return type 'int' must match previous return type 'void' when block literal has unspecified explicit return type}}
  13   };
  14
  15   int (^Y) (void)  = ^{
  16     if (3)
  17       return 1;
  18     else
  19       return; // expected-error {{return type 'void' must match previous return type 'int' when block literal has unspecified explicit return type}}
  20   };
  21
  22   char *(^Z)(void) = ^{
  23     if (3)
  24       return "";
  25     else
  26       return (char*)0;
  27   };
  28
  29   double (^A)(void) = ^ { // expected-error {{incompatible block pointer types initializing 'double (^)(void)' with an expression of type 'float (^)(void)'}}
  30     if (1)
  31       return (float)1.0;
  32     else
  33       if (2)
  34         return (double)2.0; // expected-error {{return type 'double' must match previous return type 'float' when block literal has unspecified explicit return type}}
  35     return 1; // expected-error {{return type 'int' must match previous return type 'float' when block literal has unspecified explicit return type}}
  36   };
  37   char *(^B)(void) = ^{
  38     if (3)
  39       return "";
  40     else
  41       return 2; // expected-error {{return type 'int' must match previous return type 'char *' when block literal has unspecified explicit return type}}
  42   };
  43
  44   return ^{ return 1; }; // expected-error {{incompatible block pointer types returning 'int (^)(void)' from a function with result type 'CL' (aka 'void (^)(void)')}}
  45 }
  46
  47 typedef int (^CL2)(void);
  48
  49 CL2 foo2(void) {
  50   return ^{ return 1; };
  51 }
  52
  53 typedef unsigned int * uintptr_t;
  54 typedef char Boolean;
  55 typedef int CFBasicHash;
  56
  57 #define INVOKE_CALLBACK2(P, A, B) (P)(A, B)
  58
  59 typedef struct {
  60     Boolean (^isEqual)(const CFBasicHash *, uintptr_t stack_value_or_key1, uintptr_t stack_value_or_key2, Boolean is_key);
  61 } CFBasicHashCallbacks;
  62
  63 int foo3(void) {
  64     CFBasicHashCallbacks cb;
  65
  66     Boolean (*value_equal)(uintptr_t, uintptr_t) = 0;
  67
  68     cb.isEqual = ^(const CFBasicHash *table, uintptr_t stack_value_or_key1, uintptr_t stack_value_or_key2, Boolean is_key) {
  69       return (Boolean)(uintptr_t)INVOKE_CALLBACK2(value_equal, (uintptr_t)stack_value_or_key1, (uintptr_t)stack_value_or_key2);
  70     };
  71 }
  72
  73 static int funk(char *s) {
  74   if (^{} == ((void*)0))
  75     return 1;
  76   else
  77     return 0;
  78 }
  79 void next(void);
  80 void foo4(void) {
  81   int (^xx)(const char *s) = ^(char *s) { return 1; }; // expected-error {{incompatible block pointer types initializing 'int (^)(const char *)' with an expression of type 'int (^)(char *)'}}
  82   int (*yy)(const char *s) = funk; // expected-warning {{incompatible function pointer types initializing 'int (*)(const char *)' with an expression of type 'int (char *)'}}
  83
  84   int (^nested)(char *s) = ^(char *str) { void (^nest)(void) = ^(void) { printf("%s\n", str); }; next(); return 1; }; // expected-warning{{implicitly declaring library function 'printf' with type 'int (const char *, ...)'}} \
  85   // expected-note{{include the header <stdio.h> or explicitly provide a declaration for 'printf'}}
  86 }
  87
  88 typedef void (^bptr)(void);
  89
  90 bptr foo5(int j) {
  91   __block int i;
  92   if (j)
  93     return ^{ ^{ i=0; }(); };  // expected-error {{returning block that lives on the local stack}}
  94   return ^{ i=0; };  // expected-error {{returning block that lives on the local stack}}
  95   return (^{ i=0; });  // expected-error {{returning block that lives on the local stack}}
  96   return (void*)(^{ i=0; });  // expected-error {{returning block that lives on the local stack}}
  97 }
  98
  99 int (*funcptr3[5])(long);
 100 int sz8 = sizeof(^int (*[5])(long) {return funcptr3;}); // expected-error {{block cannot return array type}} expected-warning {{incompatible pointer to integer conversion}}
 101 int sz9 = sizeof(^int(*())()[3]{ }); // expected-error {{function cannot return array type}}
 102
 103 void foo6(void) {
 104   int (^b)(int) __attribute__((noreturn));
 105   b = ^ (int i) __attribute__((noreturn)) { return 1; };  // expected-error {{block declared 'noreturn' should not return}}
 106   b(1);
 107   int (^c)(void) __attribute__((noreturn)) = ^ __attribute__((noreturn)) { return 100; }; // expected-error {{block declared 'noreturn' should not return}}
 108 }
 109
 110
 111 void foo7(void)
 112 {
 113  const int (^BB) (void) = ^{ const int i = 1; return i; }; // OK - initializing 'const int (^)(void)' with an expression of type 'int (^)(void)'
 114
 115  const int (^CC) (void)  = ^const int{ const int i = 1; return i; };
 116
 117
 118   int i;
 119   int (^FF) (void)  = ^{ return i; }; // OK
 120   int (^EE) (void)  = ^{ return i+1; }; // OK
 121
 122   __block int j;
 123   int (^JJ) (void)  = ^{ return j; }; // OK
 124   int (^KK) (void)  = ^{ return j+1; }; // OK
 125
 126   __block const int k;
 127   const int cint = 100;
 128
 129   int (^MM) (void)  = ^{ return k; };
 130   int (^NN) (void)  = ^{ return cint; };
 131 }
 132
 133 // rdar://11069896
 134 void (^blk)(void) = ^{
 135     return (void)0; // expected-warning {{void block literal should not return void expression}}
 136 };
 137
 138 // rdar://13463504
 139 enum Test8 { T8_a, T8_b, T8_c };
 140 void test8(void) {
 141   extern void test8_helper(int (^)(int));
 142   test8_helper(^(int flag) { if (flag) return T8_a; return T8_b; });
 143 }
 144 void test8b(void) {
 145   extern void test8_helper2(char (^)(int)); // expected-note {{here}}
 146   test8_helper2(^(int flag) { if (flag) return T8_a; return T8_b; }); // expected-error {{passing 'enum Test8 (^)(int)' to parameter of type 'char (^)(int)'}}
 147 }