IV35414: XLC FAILS TO IDENTIFY INVALID RESTRICT KEYWORD USE

March 2013 PTF for XL C/C++ for AIX, V12.1

APAR status

• Closed as program error.

Error description

• The following testcase attempts to use the "restrict" cv
  qualifier for a pointer to function but the usage is incorrect
  (line 2 and line 4). xlC compiler fails to identify the invalid
  usage on line 4 and also produces Internal Compiler Error if
  the test case is compiled at -O2.
  
  ===== TESTCASE:
  $cat xlc12_defect_invalidrestrict.c
  typedef void (* function_ptr_t)(void);
  inline void invoke_function(function_ptr_t __restrict__
  function) {
  }
  inline void invoke_function2(void (* __restrict__
  function)(void)) {
  }
  void some_function(void) {
  
  signed main(void) {
     invoke_function(&some_function);
     invoke_function2(&some_function);
     return 0;
  }
  
  ===== ACTUAL OUTPUT:
  $xlC -+ xlc12_defect_invalidrestrict.c
  "xlc12_defect_invalidrestrict.c", line 2.13: 1540-2606 (W)
  "restrict" can only qualify a pointer or reference type.  The
  "restrict" keyword is ignored.
  $
  $xlC -+ xlc12_defect_invalidrestrict.c -O
  "xlc12_defect_invalidrestrict.c", line 2.13: 1540-2606 (W)
  "restrict" can only qualify a pointer or reference type.  The
  "restrict" keyword is ignored.
      1500-004: (U) INTERNAL COMPILER ERROR while compiling ----.
   Compilation ended.  Contact your Service Representative and
  provide the following information: Internal abort. For more
  information visit:
  http://www.ibm.com/support/docview.wss?uid=swg21110810
  
  ===== EXPECTED OUTPUT:
  Issue warning messages for both line 2 and 4, and do not
  produce Internal Compiler Error with -O.
  

Local fix

• Correct the test case syntax.
  

Problem summary

• PROBLEM DESCRIPTION: The compiler allowed an invalid use of
  restrict on a pointer to function
  
  USERS AFFECTED: users of the restrict keyword on a pointer to
  function
  

Problem conclusion

• The problem has been resolved
  

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:

  LI77347 LI77410

Fix information

• Fixed component name

  XL C/C++ FOR AI

• Fixed component ID

  5725C7200

Applicable component levels

• RC10 PSY U858524

     UP C