*** glibc detected *** ./a.out: free(): invalid pointer: 0x087db318 ***

[kapil1089thekin]

When I am calling this function:

                
set<int> e_transition(set<int> s)       {
               set<int> eSet;
               return(s);
}

as:

set<int> startstate;
set<int> set;
set.insert(30);
 startState = nfa1.e_transition(set);

If I don't call it i.e if I make the calling statement a comment, I don't get the error, interestingly same code i took to another machine it was working, so simple function yet killing me.

Error details from $

======= Backtrace: =========
/lib/libc.so.6[0xa0e261]
/usr/lib/libstdc++.so.6(_ZdlPv+0x22)[0x4249f2]
./a.out[0x804cd0f]
./a.out[0x804c60e]
./a.out[0x804b7e4]
./a.out[0x804a7d2]
./a.out[0x804a138]
./a.out[0x8048f75]
./a.out[0x8049be3]
./a.out[0x8048de2]
/lib/libc.so.6(__libc_start_main+0xe6)[0x9b6bb6]
./a.out[0x8048c61]
======= Memory map: ========
0030c000-00329000 r-xp 00000000 fd:00 14180      /lib/libgcc_s-4.4.2-20091027.so.1
00329000-0032a000 rw-p 0001c000 fd:00 14180      /lib/libgcc_s-4.4.2-20091027.so.1
0036d000-0045b000 r-xp 00000000 fd:00 246004     /usr/lib/libstdc++.so.6.0.13
0045b000-0045f000 r--p 000ed000 fd:00 246004     /usr/lib/libstdc++.so.6.0.13
0045f000-00461000 rw-p 000f1000 fd:00 246004     /usr/lib/libstdc++.so.6.0.13
00461000-00467000 rw-p 00000000 00:00 0 
005c4000-005c5000 r-xp 00000000 00:00 0          [vdso]
0097e000-0099c000 r-xp 00000000 fd:00 245998     /lib/ld-2.11.so
0099c000-0099d000 r--p 0001d000 fd:00 245998     /lib/ld-2.11.so
0099d000-0099e000 rw-p 0001e000 fd:00 245998     /lib/ld-2.11.so
009a0000-00b0e000 r-xp 00000000 fd:00 245194     /lib/libc-2.11.so
00b0e000-00b0f000 ---p 0016e000 fd:00 245194     /lib/libc-2.11.so
00b0f000-00b11000 r--p 0016e000 fd:00 245194     /lib/libc-2.11.so
00b11000-00b12000 rw-p 00170000 fd:00 245194     /lib/libc-2.11.so
00b12000-00b15000 rw-p 00000000 00:00 0 
00b3a000-00b62000 r-xp 00000000 fd:00 91954      /lib/libm-2.11.so
00b62000-00b63000 r--p 00027000 fd:00 91954      /lib/libm-2.11.so
00b63000-00b64000 rw-p 00028000 fd:00 91954      /lib/libm-2.11.so
08048000-08051000 r-xp 00000000 fd:00 170801     /home/kapil/iitKGP/systems_computing_lab1/assign3/a.out
08051000-08052000 rw-p 00008000 fd:00 170801     /home/kapil/iitKGP/systems_computing_lab1/assign3/a.out
087d9000-087fa000 rw-p 00000000 00:00 0          [heap]
b7830000-b7832000 rw-p 00000000 00:00 0 
b7855000-b7857000 rw-p 00000000 00:00 0 
bfbd5000-bfbea000 rw-p 00000000 00:00 0          [stack]
not foundAborted (core dumped)

Is fixing it tough, How can I?

[Salem]

Why do you presume this is the problem?

You're observing cause and effect.
When it comes to memory corruption, where the problem is may have nothing to do with where the problem shows up.

Try running the program under valgrind (with the "drop into debugger" option when a problem is detected).

Eg.

char *p = new[10];
p[10] = 0; // oops
delete [ ] p;  // oops
// lots more code
set<int> startstate;
set<int> set;
set.insert(30);
 startState = nfa1.e_transition(set);
// and crash!

You need to find prior "oops" code. Just because it didn't immediately crash doesn't make it bug-free.

[kapil1089thekin]

What code is this for? can you explain it more?

Is the function definition and the calling is OK?

[Salem]

It's an example!

If you put the 5 or so lines of what you posted into a new main(), then chances are it will work just as you expect.

If it does work as you expect, then the problem in your actual code is ELSEWHERE.

You need to start looking elsewhere.