Re: [Valgrind-users] uninitialized value error with packed structure

[David L <id...@gm...>]

On Thu, May 14, 2009 at 12:33 AM, Julian Seward wrote:
>
>> Hmm, that's ungood.  Can you send details of the precise gcc version,
>> the compilation flags, and the what kind of processor you're running on?

I'm running on a fedora 10 x86 box:


valgrind --version
valgrind-3.4.1


g++ --version
g++ (GCC) 4.3.2 20081105 (Red Hat 4.3.2-7)

g++ -g3 -o foo main.cpp


valgrind --track-origins=yes foo
==3121== Memcheck, a memory error detector.
==3121== Copyright (C) 2002-2008, and GNU GPL'd, by Julian Seward et al.
==3121== Using LibVEX rev 1884, a library for dynamic binary translation.
==3121== Copyright (C) 2004-2008, and GNU GPL'd, by OpenWorks LLP.
==3121== Using valgrind-3.4.1, a dynamic binary instrumentation framework.
==3121== Copyright (C) 2000-2008, and GNU GPL'd, by Julian Seward et al.
==3121== For more details, rerun with: -v
==3121==
==3121== Conditional jump or move depends on uninitialised value(s)
==3121==    at 0x804852F: main (main.cpp:11)
==3121==  Uninitialised value was created by a heap allocation
==3121==    at 0x400674E: operator new(unsigned int) (vg_replace_malloc.c:224)
==3121==    by 0x8048510: main (main.cpp:9)
d equals zero.
myclass size is 2
==3121==
==3121== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 16 from 1)
==3121== malloc/free: in use at exit: 2 bytes in 1 blocks.
==3121== malloc/free: 1 allocs, 0 frees, 2 bytes allocated.
==3121== For counts of detected errors, rerun with: -v
==3121== searching for pointers to 1 not-freed blocks.
==3121== checked 89,756 bytes.
==3121==
==3121== LEAK SUMMARY:
==3121==    definitely lost: 2 bytes in 1 blocks.
==3121==      possibly lost: 0 bytes in 0 blocks.
==3121==    still reachable: 0 bytes in 0 blocks.
==3121==         suppressed: 0 bytes in 0 blocks.
==3121== Rerun with --leak-check=full to see details of leaked memory.



cat /proc/cpuinfo
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 15
model		: 3
model name	: Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping	: 4
cpu MHz		: 3000.000
cache size	: 1024 KB
fdiv_bug	: no
hlt_bug		: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 3
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat
pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe constant_tsc up
pebs bts pni monitor ds_cpl cid xtpr
bogomips	: 5984.98
clflush size	: 64
power management:


Thanks,

                David