PH45307: NESTED ENCLAVE RESTRICTION WHEN RUNNING C/C++ IN A MULTITHREADED ENVIRONMENT.

APAR status

• Closed as documentation error.

Error description

• An abends0c4 is happening in Language Environment module
  CEEPMDEL when using pthreads in a multithreaded environment.
  
  ANALYSIS:
  The abend is happening because the customer is running C/C++ in
  a multithreaded environment and creating a nested enclave.
  Doing so can cause unpredictable results and is not supported.
  
  KNOWN IMPACT:
  The application will fail.
  
  VERIFICATION STEPS:
  The customer must be running C/C++ in a multithreaded
  environment and must be creating a nested enclave.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of z/OS XL C/C++ who create a nested enclave.          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * When C/C++ application is trying to create a nested enclave  *
  * in a multithread environment, the application may encounter  *
  * an ABEND S0C4.                                               *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  

Problem conclusion

• z/OS Language Environment Programming Guide
  -> Chapter - Using nested enclaves
  -> Other nested enclave considerations
  Add the following paragraph after 'COBOL multithreading
  considerations':
  
  C/C++ multithreading considerations
  When C/C++ is running in a multithread environment, creating
  nested enclaves is not supported. Violation of this rule is
  likely to cause unpredictable results.
  

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

Applicable component levels