Strange R__unzip error when reading ROOT 4 written files

ROOT
1

Dear experts,

some BaBar users ran into a R__unzip error when they tried to read with ROOT 5 some
event files which were written with ROOT4:

R__unzip: error during decompression
followed by some error messages from the BaBar software.

Playing around at the ROOT prompt I found that if I try to FindObjectAny(“name”) some
objects which are derived from TTree, it depends on the order of the FindObjectAny()s
if everything works or if I get the R__unzip error. One time I got a segfault instead of the
R__unzip and a traceback that may be usefull:

root [36] TXNetFile f2("root://kanolb-a:1094///store/PRskims/R18/18.6.0b/Tau11/88/Tau11_8847.01.root$
root [37] f2.FindObjectAny(“hdr”)
(const class TObject*)0xc6aa568
root [38] f2.FindObjectAny(“cnd”)
(const class TObject*)0xcac9fb0
root [39] f2.FindObjectAny(“tag”)
(const class TObject*)0xca48c78
root [40] f2.Close()

******* everything works fine for ‘hdr’ - ‘cnd’ - ‘tag’

root [41] TXNetFile f2("root://kanolb-a:1094///store/PRskims/R18/18.6.0b/Tau11/88/Tau11_8847.01.root$
root [42] f2.FindObjectAny(“hdr”)
(const class TObject*)0xc5380a8
root [43] f2.FindObjectAny(“tag”)
(const class TObject*)0xc9c1ca8
root [44] f2.FindObjectAny(“cnd”)

*** Break *** segmentation violation
Generating stack trace…
/usr/bin/addr2line: Kanga: No such file or directory
/usr/bin/addr2line: Kanga: No such file or directory
0x00b57b3a in R__Inflate_block + 0xb3 from ./shlib/Linux24SL3_i386_gcc323/ldlink/libCore.so
0x00b57bb0 in R__Inflate + 0x4d from ./shlib/Linux24SL3_i386_gcc323/ldlink/libCore.so
0x00b57dfa in R__unzip + 0x1bb from ./shlib/Linux24SL3_i386_gcc323/ldlink/libCore.so
0x00a371e0 in TKey::ReadObj() + 0x2ae from ./shlib/Linux24SL3_i386_gcc323/ldlink/libCore.so
0x00a21e39 in TDirectory::FindObjectAny(char const*) const + 0x223 from ./shlib/Linux24SL3_i386_gcc323/ldlink/libCore.so

Do you have an idea what is going wrong here?
If I do the same exercise with ROOT 4, everything works fine.

Thanks,
Matthias

2

Matthias,

Which version of ROOT5 are you using?
Coould you try with version 5.13/06 ?

Rene

3

Hi Rene,
sorry for the late response, but I’m on a workshop with limited network access …

[quote=“brun”]Matthias,

Which version of ROOT5 are you using?
Coould you try with version 5.13/06 ?

Rene[/quote]

It’s ROOT 5.10/00c and 5.10/00f. To use 5.13/06 I have to install it at SLAC (hopefully it
will compile for all platforms used at SLAC) and I have to recompile a bunch of BaBar
packages, so it will take some time.
Do you have a particular change between 5.10/00 and 5.13/06 in mind, or is this more a
"please try the latest version first" advice?

Thanks,
Matthias

4

Hi Rene,
I don’t know why, but switching to ROOT 5.13/06 seems to help. I now will try to build
and install 5.13/06 at SLAC for all platforms which we support. Let’s keep our fingers
crossed that that will work.

Thanks for your help,
Matthias

[quote=“matthiasSteinke”]Hi Rene,
sorry for the late response, but I’m on a workshop with limited network access …

[quote=“brun”]Matthias,

Which version of ROOT5 are you using?
Coould you try with version 5.13/06 ?

Rene[/quote]

It’s ROOT 5.10/00c and 5.10/00f. To use 5.13/06 I have to install it at SLAC (hopefully it
will compile for all platforms used at SLAC) and I have to recompile a bunch of BaBar
packages, so it will take some time.
Do you have a particular change between 5.10/00 and 5.13/06 in mind, or is this more a
"please try the latest version first" advice?

Thanks,
Matthias[/quote]