clang/test/SemaCXX/warn-new-overaligned.cpp

   1 // RUN: %clang_cc1 -triple=x86_64-pc-linux-gnu -Wover-aligned -verify %s
   2
   3 namespace test1 {
   4 struct Test {
   5   template <typename T>
   6   struct SeparateCacheLines {
   7     T data;
   8   } __attribute__((aligned(256)));
   9
  10   SeparateCacheLines<int> high_contention_data[10];
  11 };
  12
  13 void helper() {
  14   Test t;
  15   new Test;  // expected-warning {{type 'Test' requires 256 bytes of alignment and the default allocator only guarantees}}
  16   new Test[10];  // expected-warning {{type 'Test' requires 256 bytes of alignment and the default allocator only guarantees}}
  17 }
  18 }
  19
  20 namespace test2 {
  21 class Test {
  22   typedef int __attribute__((aligned(256))) aligned_int;
  23   aligned_int high_contention_data[10];
  24 };
  25
  26 void helper() {
  27   Test t;
  28   new Test;  // expected-warning {{type 'Test' requires 256 bytes of alignment and the default allocator only guarantees}}
  29   new Test[10];  // expected-warning {{type 'Test' requires 256 bytes of alignment and the default allocator only guarantees}}
  30 }
  31 }
  32
  33 namespace test3 {
  34 struct Test {
  35   template <typename T>
  36   struct SeparateCacheLines {
  37     T data;
  38   } __attribute__((aligned(256)));
  39
  40   void* operator new(unsigned long) {
  41     return 0; // expected-warning {{'operator new' should not return a null pointer unless it is declared 'throw()'}}
  42   }
  43
  44   SeparateCacheLines<int> high_contention_data[10];
  45 };
  46
  47 void helper() {
  48   Test t;
  49   new Test;
  50   new Test[10];  // expected-warning {{type 'Test' requires 256 bytes of alignment and the default allocator only guarantees}}
  51 }
  52 }
  53
  54 namespace test4 {
  55 struct Test {
  56   template <typename T>
  57   struct SeparateCacheLines {
  58     T data;
  59   } __attribute__((aligned(256)));
  60
  61   void* operator new[](unsigned long) {
  62     return 0; // expected-warning {{'operator new[]' should not return a null pointer unless it is declared 'throw()'}}
  63   }
  64
  65   SeparateCacheLines<int> high_contention_data[10];
  66 };
  67
  68 void helper() {
  69   Test t;
  70   new Test;  // expected-warning {{type 'Test' requires 256 bytes of alignment and the default allocator only guarantees}}
  71   new Test[10];
  72 }
  73 }