This command (generate by libtool) g++ -o test1 -g AbstractTimeStepsGenerator.o Coefficients.o Covariates.o Data.o FixedTimeStepsGenerator.o LinearProduct.o Path.o LinearProduct_test.o Coefficients_test.o basic_test.o main_test.o ScratchPad_test.o ScratchDataProducer_test.o Covariates_test.o Data_samples.o EnvPath_samples.o Rstub.o -lboost_unit_test_framework Generates these errors: LinearProduct.o(.gnu.linkonce.r._ZTIN6mspath17DataLinearProductE +0x8):/usr/include/c++/3.3/bits/stl_tree.h:159: undefined reference to `typeinfo for mspath::AbstractLinearProduct' LinearProduct.o(.gnu.linkonce.r._ZTIN6mspath26PathDependentLinearProductE+0x8):/usr/include/c++/3.3/bits/stl_tree.h:159: undefined reference to `typeinfo for mspath::AbstractLinearProduct' LinearProduct_test.o(.gnu.linkonce.r._ZTIN6mspath21ConstantLinearProductE+0x8):/usr/include/boost/test/test_tools.hpp:427: undefined reference to `typeinfo for mspath::AbstractLinearProduct' The type AbstractLinearProduct is defined in the header for LinearProduct, which is included in the .cc file. Googling, it sounds as if complaints about typeinfo may signal missing RTTI. However, I did not compile with no-rtti, and the included files referenced are all source files. I do use some dynamic_cast's, though none of them mention AbstractLinearProduct explicitly. I'd appreciate any pointers you can offer. Is it possible that because AbstractLinearProduct is never instantiated (it can't be, having pure virtual functions), some needed info isn't being generated that's needed elsewhere? $ g++ --version g++ (GCC) 3.3.5 (Debian 1:3.3.5-8) Running on Debian GNU/Linux, 2.4.27 kernel (mostly the Debian testing distribution). -- Ross Boylan wk: (415) 502-4031 530 Parnassus Avenue (Library) rm 115-4 ross@xxxxxxxxxxxxxxxx Dept of Epidemiology and Biostatistics fax: (415) 476-9856 University of California, San Francisco San Francisco, CA 94143-0840 hm: (415) 550-1062