Fixes are available
XL C/C++ for Blue Gene/Q Fix Pack 12 (May 2015 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 14 (May 2016 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 15 (October 2017 Update) for 12.1
February 2013 Update for XL C/C++ for Blue Gene/Q, V12.1
May 2013 Update for XL C/C++ for Blue Gene/Q, V12.1
XL C/C++ for Blue Gene/Q Fix Pack 5 (August 2013 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 6 (November 2013 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 7 (February 2014 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 8 (May 2014 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 9 (August 2014 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 10 (November 2014 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 11 (February 2015 Update) for 12.1
XL C/C++ for Blue Gene/Q Fix Pack 13 (August 2015 Update) for 12.1
APAR status
Closed as program error.
Error description
Compiling with -O2 and inlining enabled, with a ?: conditional as a template function parameter, is causing valid code to be optimized away, resulting in invalid code behaviour. In the example below, invalid stack data is accessed, and output is incorrect: ==== TEST CASE ==== #include <iostream> struct MyStruct { template <typename T> static void print( T const & x ) { std::cout << x; } }; int main(int argc, char *argv[]) { MyStruct::print(argc == 1?"test1":"test2"); } $ xlC -q64 -O2 apar.cpp $ ./a.out | od -c 0000000 º Ü 017 þ à Ý ð \r º Ü 017 þ à Ý ð \r 0000020 $ $ ./a.out | od -x 0000000 badc 0ffe e0dd f00d badc 0ffe e0dd f00d 0000020 $
Local fix
- Disable inlining - Convert ?: conditional into an IF statement
Problem summary
PROBLEM DESCRIPTION: Processing of the ?: ternary operator is ignoring the memory location of the result, leading to incorrect code and behaviour. USERS AFFECTED: Users of the ?: ternary operator, the << operator, and optimization.
Problem conclusion
The issue has been corrected.
Temporary fix
Comments
APAR Information
APAR number
LI77230
Reported component name
XL C/C++ FOR BG
Reported component ID
5799AG100
Reported release
C10
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2013-02-21
Closed date
2013-02-21
Last modified date
2013-02-21
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++ FOR BG
Fixed component ID
5799AG100
Applicable component levels
Document Information
Modified date:
05 September 2024