Error due to "static const int"

ROOT
1

Hi,

     I have a class "Alpgen".  If in the .h I include these lines:

static const int Sample = 2;
static const int WhichJet = 3;
static const int WhichPhot = 3;

I get the following error.

root [0]
Processing Analysis.C…
dlopen error: /home/sushil/Wisconsin/Alpgen/Combined/./Alpgen.so: undefined symbol: _ZN6Alpgen9WhichPhotE
Load Error: Failed to load Dynamic link library /home/sushil/Wisconsin/Alpgen/Combined/./Alpgen.so

If I do not include these lines then code works fine.  One can see it  at the following link:

schauhan.web.cern.ch/schauhan/BSM/Combined/

It seems some library is needed to be load before i run my .so.

Could someone sugggest how to solve it.

Thanks and with best,
sushil

2

You should look in your shared libs the one containing a symbol (use nm mylib.so) looking like _ZN6Alpgen9WhichPhotE

Rene

3

Hi,

I did “nm Alpgen.so” and it shows me the following for the symbol “_ZN6Alpgen9WhichPhotE”

…
…
…0000ce8a T _ZN6Alpgen8LoadTreeEx
U _ZN6Alpgen8WhichJetE
U _ZN6Alpgen9WhichPhotE <---------THIS IS THE SYMBOLE
0000aa3c W ZN6AlpgenaSERKS
…
…

with best,
sushil

4

Hi,
As “nm Alpgen.so” says the symbol is undefined so may be the reason is that till now I was declaring Sample in my class “Alpgen” as:

static const int Sample= 2;

NOW I added one more line in my .h (outside my class definiton) file which is:

const int Alpgen::Sample; (because it is a static data member!!)

But this also gives an error as listed below:

/tmp/ccsMgafv.o(.rodata+0x0): multiple definition of Alpgen::Sample' /tmp/ccemydi0.o(.rodata+0x0): first defined here /tmp/ccsMgafv.o(.rodata+0x4): multiple definition ofAlpgen::WhichJet’
/tmp/ccemydi0.o(.rodata+0x4): first defined here
/tmp/ccsMgafv.o(.rodata+0x8): multiple definition of Alpgen::WhichPhot' /tmp/ccemydi0.o(.rodata+0x8): first defined here /tmp/ccsMgafv.o(.rodata+0xc): multiple definition ofAlpgen::NJets_upto’

with best,
sushil

5

[quote]NOW I added one more line in my .h (outside my class definiton) file which is:

const int Alpgen::Sample; (because it is a static data member!!) [/quote]You MUST add this line to your .cc file and NOT to your .h file. The compiler must see that line exactly once.

Cheers,
Philippe.

6

Thanks. It works now.

with best,
sushil