LI81525: INVALID DESTRUCTOR CALL INSERTED AFTER __BUILTIN_CONSTANT_P() BUILTIN

APAR status

• Closed as program error.

Error description

• Usage of the __builtin_constant_p() builtin with a class
  constructor is leading to the generation of a paired destructor
  for the object.  After the builtin is evaluated, the destructor
  is still present in the code, even though no object is created,
  leading to an invalid delete/free() memory call for objects
  never initialized.
  
  
     === TEST CASE ===
  
  #include <cstdio>
  
  int main(int argc, char *argv[]) {
      class Test {
      public:
          Test() {
              std::printf("Test::Test\n");
          }
  
          ~Test() {
              std::printf("Test::~Test\n");
          }
      };
      __builtin_constant_p(Test());
  }
  
  
  $ xlc++ test.cpp
  $ ./a.out
  Test::~Test
  $
  

Local fix

Problem summary

• PROBLEM DESCRIPTION:
  Implicit destructor calls will remain while the initialization
  inside a __builtin_constant_p call will be discarded.
  
  USERS AFFECTED:
  __builtin_constant_p calls, which contain implicit destructor
  calls.
  

Problem conclusion

• The compiler will now evaluate the __builtin_constant_p builtin
  before the generation of the implicit destructor call.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  XL C/C++ LINUX

• Fixed component ID

  5725C7310

Applicable component levels