Running ROOT in debug mode, this is the print that I get:
Program received signal SIGABRT, Aborted.
0x0000003587c32635 in raise () from /lib64/libc.so.6
Missing separate debuginfos, use: debuginfo-install expat-2.0.1-11.el6_2.x86_64 fontconfig-2.8.0-3.el6.x86_64 freetype-2.3.11-14.el6_3.1.x86_64 glibc-2.12-1.132.el6_5.4.x86_64 gsl-1.13-1.el6.x86_64 keyutils-libs-1.4-4.el6.x86_64 krb5-libs-1.10.3-10.el6_4.6.x86_64 libX11-1.5.0-4.el6.x86_64 libXau-1.0.6-4.el6.x86_64 libXcursor-1.1.13-6.20130524git8f677eaea.el6.x86_64 libXext-1.3.1-2.el6.x86_64 libXfixes-5.0-3.el6.x86_64 libXft-2.3.1-2.el6.x86_64 libXpm-3.5.10-2.el6.x86_64 libXrender-0.9.7-2.el6.x86_64 libcom_err-1.41.12-18.el6.x86_64 libgcc-4.4.7-4.el6.x86_64 libjpeg-turbo-1.2.1-3.el6_5.x86_64 libpng-1.2.49-1.el6_2.x86_64 libselinux-2.0.94-5.3.el6_4.1.x86_64 libstdc+±4.4.7-4.el6.x86_64 libxcb-1.8.1-1.el6.x86_64 openssl-1.0.1e-16.el6_5.15.x86_64 pcre-7.8-6.el6.x86_64 zlib-1.2.3-29.el6.x86_64
(gdb) bt
#0 0x0000003587c32635 in raise () from /lib64/libc.so.6
#1 0x0000003587c33e15 in abort () from /lib64/libc.so.6
#2 0x0000003587c2b75e in __assert_fail_base () from /lib64/libc.so.6
#3 0x0000003587c2b820 in __assert_fail () from /lib64/libc.so.6
#4 0x00007ffff20892ba in RooChebychev::analyticalIntegral(int, char const*) const () from /opt/root_v5.34.18/lib/libRooFit.so
#5 0x00007ffff30cf3ba in RooAbsPdf::analyticalIntegralWN(int, RooArgSet const*, char const*) const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#6 0x00007ffff31f1b34 in RooRealIntegral::evaluate() const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#7 0x00007ffff30e7772 in RooAbsReal::traceEval(RooArgSet const*) const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#8 0x00007ffff31ef862 in RooRealIntegral::getValV(RooArgSet const*) const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#9 0x00007ffff3107550 in RooAddPdf::updateCoefficients(RooAddPdf::CacheElem&, RooArgSet const*) const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#10 0x00007ffff310ae7c in RooAddPdf::evaluate() const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#11 0x00007ffff30d3fee in RooAbsPdf::getValV(RooArgSet const*) const () from /opt/root_v5.34.18/lib/libRooFitCore.so
#12 0x00007ffff30c7120 in RooAbsOptTestStatistic::initSlave(RooAbsReal&, RooAbsData&, RooArgSet const&, char const*, char const*) () from /opt/root_v5.34.18/lib/libRooFitCore.so
#13 0x00007ffff30c7c01 in RooAbsOptTestStatistic::RooAbsOptTestStatistic(char const*, char const*, RooAbsReal&, RooAbsData&, RooArgSet const&, char const*, char const*, int, RooFit::MPSplit, bool, bool, bool) () from /opt/root_v5.34.18/lib/libRooFitCore.so
#14 0x00007ffff31c1413 in RooNLLVar::RooNLLVar(char const*, char const*, RooAbsPdf&, RooAbsData&, RooArgSet const&, bool, char const*, char const*, int, RooFit::MPSplit, bool, bool, bool, bool) () from /opt/root_v5.34.18/lib/libRooFitCore.so
#15 0x00007ffff30d3177 in RooAbsPdf::createNLL(RooAbsData&, RooLinkedList const&) () from /opt/root_v5.34.18/lib/libRooFitCore.so
#16 0x00007ffff30cfd21 in RooAbsPdf::fitTo(RooAbsData&, RooLinkedList const&) () from /opt/root_v5.34.18/lib/libRooFitCore.so
#17 0x00007ffff30cb661 in RooAbsPdf::fitTo(RooAbsData&, RooCmdArg const&, RooCmdArg const&, RooCmdArg const&, RooCmdArg const&, RooCmdArg const&, RooCmdArg const&, RooCmdArg const&, RooCmdArg const&) () from /opt/root_v5.34.18/lib/libRooFitCore.so
#18 0x00007ffff091638d in RooFit_test() () from /.data/alpigiani/CODE/BackgroundBDTdependence/./RooFit_test_C.so
#19 0x00007ffff0917119 in G__RooFit_test_C_ACLiC_dict__0_4071(G__value*, char const*, G__param*, int) () from /.data/alpigiani/CODE/BackgroundBDTdependence/./RooFit_test_C.so
#20 0x00007ffff6aa9b79 in Cint::G__ExceptionWrapper(int ()(G__value, char const*, G__param*, int), G__value*, char*, G__param*, int) () from /opt/root_v5.34.18/lib/libCint.so
#21 0x00007ffff6b4df01 in G__execute_call () from /opt/root_v5.34.18/lib/libCint.so
#22 0x00007ffff6b4ed42 in G__call_cppfunc () from /opt/root_v5.34.18/lib/libCint.so
#23 0x00007ffff6b2af18 in G__interpret_func () from /opt/root_v5.34.18/lib/libCint.so
#24 0x00007ffff6b18ccb in G__getfunction () from /opt/root_v5.34.18/lib/libCint.so
#25 0x00007ffff6af676e in G__getitem () from /opt/root_v5.34.18/lib/libCint.so
#26 0x00007ffff6afb2e8 in G__getexpr () from /opt/root_v5.34.18/lib/libCint.so
#27 0x00007ffff6b047f8 in G__calc_internal () from /opt/root_v5.34.18/lib/libCint.so
#28 0x00007ffff6b89e33 in G__process_cmd () from /opt/root_v5.34.18/lib/libCint.so
#29 0x00007ffff7851516 in TCint::ProcessLine(char const*, TInterpreter::EErrorCode*) () from /opt/root_v5.34.18/lib/libCore.so
#30 0x00007ffff784ec13 in TCint::ProcessLineSynch(char const*, TInterpreter::EErrorCode*) () from /opt/root_v5.34.18/lib/libCore.so
#31 0x00007ffff77baca8 in TApplication::ExecuteFile(char const*, int*, bool) () from /opt/root_v5.34.18/lib/libCore.so
#32 0x00007ffff77b8fb3 in TApplication::ProcessLine(char const*, bool, int*) () from /opt/root_v5.34.18/lib/libCore.so
#33 0x00007ffff740cd7b in TRint::HandleTermInput() () from /opt/root_v5.34.18/lib/libRint.so
#34 0x00007ffff788bb3e in TUnixSystem::CheckDescriptors() () from /opt/root_v5.34.18/lib/libCore.so
#35 0x00007ffff788bce3 in TUnixSystem::DispatchOneEvent(bool) () from /opt/root_v5.34.18/lib/libCore.so
#36 0x00007ffff78113e6 in TSystem::InnerLoop() () from /opt/root_v5.34.18/lib/libCore.so
#37 0x00007ffff7812dcb in TSystem::Run() () from /opt/root_v5.34.18/lib/libCore.so
#38 0x00007ffff77b6d5f in TApplication::Run(bool) () from /opt/root_v5.34.18/lib/libCore.so
#39 0x00007ffff740e304 in TRint::Run(bool) () from /opt/root_v5.34.18/lib/libRint.so
#40 0x000000000040103c in main ()