[Valgrind-users] DESPERATE: Receiving confusing warnings during very short execution phase

[cleca <cle...@un...>]

I am receiving numerous very confusing warnings by valgrind on a tiny initial
execution fragment of a large program.

The program fragment is as follows:

int main(int argc, const char* argv[]) {
  openlog  (NAME_OF_PROGRAM, LOG_NDELAY , LOG_USER);  
  syslog   (LOG_NOTICE, "Program is starting up at process id %d",
getpid());
  exit(1);
...
}

and valgrind presents many complaints (see below) for syslog. The main
function is part of a large c++ program, to which several libraries get
linked. On the other hand, if I run valgrind on a program consisting ONLY of
the above function, everything is fine.

I tried to pinpoint the responsible component, but since the code base is
rather large I am getting more and more desperate and see no strategy any
more for doing this...

== PASTE of parts of the complaints ==
 Invalid read of size 8
==19525==    at 0x6E6E2CA: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86416: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Address 0x757d650 is 16 bytes inside a block of size 20 alloc'd
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E86431: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Invalid read of size 8
==19525==    at 0x6E6E2D3: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86416: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Address 0x757d658 is 4 bytes after a block of size 20 alloc'd
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E86431: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Conditional jump or move depends on uninitialised value(s)
==19525==    at 0x6E6E2F2: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86416: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Uninitialised value was created by a heap allocation
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E87B86: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Use of uninitialised value of size 8
==19525==    at 0x6E6F6C4: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86416: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Uninitialised value was created by a heap allocation
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E87B86: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Use of uninitialised value of size 8
==19525==    at 0x6E6F6C8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86416: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Uninitialised value was created by a heap allocation
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E87B86: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Invalid read of size 8
==19525==    at 0x6E6ECA4: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86416: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Address 0x757d6b0 is 16 bytes inside a block of size 21 alloc'd
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E86431: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Conditional jump or move depends on uninitialised value(s)
==19525==    at 0x6E6FD19: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E863E2: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Uninitialised value was created by a heap allocation
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E87B86: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525== 
==19525== Conditional jump or move depends on uninitialised value(s)
==19525==    at 0x6E86402: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E88052: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)
==19525==  Uninitialised value was created by a heap allocation
==19525==    at 0x4C25D8C: malloc (vg_replace_malloc.c:270)
==19525==    by 0x6E87B86: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86C87: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6E86DA8: ??? (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EBFA8C: __vsyslog_chk (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x6EC00BF: syslog (in
/home/cap/workspace/kademlia2/libs/libc.so.6)
==19525==    by 0x5EB1D2: main (kademlia.cpp:211)










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