LI81497: SEGFAULT/DOUBLE-FREE CORRUPTION WHEN STD::STRING ARRAY IS INITIALIZED IN STRUCT

APAR status

• Closed as program error.

Error description

• SEGFAULT/DOUBLE-FREE CORRUPTION WHEN STD::STRING ARRAY IS
  INITIALIZED IN STRUCT USING XL C/C++FOR LINUX, V16.1
  ----------------------------------------------------------------
  
  xlc++ -std=c++11 -o test main.cpp
  
  ./test
  *** Error in `./test': double free or corruption (fasttop):
  0x000001003b130010 ***
  ======= Backtrace: =========
  /lib64/libc.so.6(cfree+0x49c)[0x3fffaba49bec]
  /lib64/libstdc++.so.6(_ZdlPv+0x20)[0x3fffabdc8d30]
  /lib64/libstdc++.so.6(_ZNSs4_Rep10_M_destroyERKSaIcE+0x18)[0x3ff
  fabe58e68]
  /lib64/libstdc++.so.6(+0x6850c)[0x3fffabda850c]
  /lib64/libstdc++.so.6(_ZNSsD1Ev+0x64)[0x3fffabe58f24]
  ./test[0x100008a0]
  ./test[0x100009b0]
  ./test[0x10000a18]
  /lib64/libc.so.6(+0x25280)[0x3fffab9d5280]
  /lib64/libc.so.6(__libc_start_main+0xc4)[0x3fffab9d5474]
  
  ================================================================
  
  Test Case:
  
  #include <array>
  #include <string>
  
  struct TestStruct
  {
    std::array<std::string, 1> arr = {{"one"}};
  };
  
  int main(void)
  {
    TestStruct s;
    return 0;
  }
  

Local fix

• N/A
  

Problem summary

• SEGFAULT/DOUBLE-FREE CORRUPTION WHEN STD::STRING ARRAY IS
  INITIALIZED IN STRUCT
  

Problem conclusion

• The problem is with the code for handling the init list, the
  code checked for presence of both an exprWithCleanups and
  cxxDefaultInitExpr but did not handle both being present.
  

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