IV47945: INCORRECT WARNING FOR "RESTRICT" WITH TYPEDEF

XL C/C++ for AIX Fix Pack 7 (January 2014 PTF) for 12.1
XL C/C++ for AIX Fix Pack 8 (March 2014 PTF) for 12.1
XL C/C++ for AIX Fix Pack 11 (February 2015 PTF) for 12.1
XL C/C++ for AIX Fix Pack 12 (May 2015 PTF) for 12.1
XL C/C++ for AIX Fix Pack 13 (August 2015 Update) for 12.1
XL C/C++ for AIX Fix Pack 14 (December 2015 Update) for 12.1
XL C/C++ for AIX Fix Pack 15 (April 2016 Update) for 12.1
XL C/C++ for AIX Fix Pack 16 (July 2016 Update) for 12.1
XL C/C++ for AIX Fix Pack 17 (November 2016 Update) for 12.1
XL C/C++ for AIX Fix Pack 18 (February 2017 Update) for 12.1
XL C/C++ for AIX Fix Pack 19 (August 2017 Update) for 12.1
XL C/C++ for AIX Fix Pack 20 (March 2018 Update) for 12.1
XL C/C++ for AIX Fix Pack 6 (December 2013 PTF) for 12.1
XL C/C++ for AIX Fix Pack 9 (July 2014 PTF) for 12.1
XL C/C++ for AIX Fix Pack 10 (October 2014 PTF) for 12.1
XL C/C++ for AIX Fix Pack 21 (January 2019 Update) for 12.1

APAR status

• Closed as program error.

Error description

• When declaring a pointer as restrict through more than one
  level of typedef, the parser incorrectly believes the
  underlying type is not a pointer and issues the warning
  1540-2606.
  
  ===== TESTCASE:
  $cat xlc12_defect_restricttypedef.cpp
  
  typedef signed * signed_ptr;
  typedef signed_ptr key_type;
  
  void func01(signed * __restrict__ p);   //========>OK
  void func02(signed_ptr __restrict__ p); //========>OK
  void func03(key_type __restrict__ p);   //========>BAD!!
  
  xlC -q'sourcetype=c++' xlc12_defect_restricttypedef.cpp -c
  "xlc12_defect_restricttypedef.cpp", line 13.6: 1540-2606 (W)
  "restrict" can only qualify a pointer or reference type.  The
  "restrict" keyword is ignored.
  
  C compiler behavior is correct which compiles the file clean.
  

Local fix

• Avoid multiple level of typedef. This is only a warning and
  does not stop compilation.
  

Problem summary

• PROBLEM DESCRIPTION: Multiple typedef is hiding the restrict
  attribute from the error checking.
  
  USERS AFFECTED: All users using multiple typedefs on restrict
  

Problem conclusion

• The issue has been solved.
  

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:

  LI77710

Fix information

• Fixed component name

  XL C/C++ FOR AI

• Fixed component ID

  5725C7200

Applicable component levels