root on Linux: can't make trees?

stefan kluth (skluth@mh1.lbl.gov)
Tue, 9 Jun 1998 17:44:30 -0700 (PDT)


Hi,

I am learning to write root trees and I am stuck at a strange problem:

persil:~/scratch> g++ -g -o treetest myclassCint.cc myclass.cc treetest.cc
-I${ROOTSYS}/include -L${ROOTSYS}/lib -lNew -lBase -lCint -lRint -lClib
-lCont -lFunc -lGraf -lGraf3d -lHist -lHtml -lMatrix -lMeta -lMinuit -lNet
-lPostscript -lProof -lTree -lUnix -lZip -lGpad -lGui -lGX11 -lX3d
-L/usr/X11R6/lib -lX11 -ldl -lXpm -lm
treetest.cc: In function `int main(int, char **)':
treetest.cc:46: warning: initialization to `int' from `float'
/tmp/cce23616: In function `myclass type_info function':
/home/skluth/scratch/myclass.cc:5: undefined reference to `TObject
type_info function'
/home/skluth/scratch/myclass.cc:5: undefined reference to `TObject
type_info node'

myclass.hh/cc defines the objects which are stored in a tree and treetest
is a simple main() which generates the objects with random numbers. The
same code works just fine on DEC unix 4 with DEC cxx 6. The line
myclass.cc:5 contains "ClassImp(myclass)".

I work on Linux persil 2.0.33 #7 Sat Apr 11 04:37:43 PDT 1998 i686 unknown

with persil:~/scratch> g++ -v
Reading specs from /usr/lib/gcc-lib/i486-linux/egcs-2.90.29/specs
gcc version egcs-2.90.29 980515 (egcs-1.0.3 release)

cheers, Stefan

---Stefan Kluth---------------Lynen Fellow----------------|\--|\-------
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