Hello, hopefully someone can help me out with this. I am trying to get GiNaC working with cygwin. I installed the cln and ginac libraries with no problems at all. I can run ginsh no problem. However, when I go to compile a sample program in the tutorial. I get a TON of errors, most saying undefined reference. I'll copy part of the error log so you can see: /usr/local/lib/libginac.a(inifcns.o): In function `_ZN5GiNaC6fsolveERKNS_2exERKNS_6symbolERKNS_7numericES8_': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/lib/libginac.a(inifcns.o):/usr/local/include/cln/object.h:216: more undefined references to `cln::cl_free_heap_object(cln::cl_heap*)' follow /usr/local/lib/libginac.a(numeric.o): In function `_ZStplIcSt11char_traitsIcESaIcEESbIT_T0_T1_ES3_RKS6_': /usr/local/include/cln/object.h:(.text+0x7): undefined reference to `cln::cl_R_ring' /usr/local/lib/libginac.a(numeric.o): In function `_ZNK5GiNaC7numeric11is_rationalEv': /usr/local/include/cln/ring.h:417: undefined reference to `cln::cl_RA_ring' /usr/local/lib/libginac.a(numeric.o): In function `_ZNK5GiNaC7numeric10is_integerEv': /usr/local/include/cln/ring.h:417: undefined reference to `cln::cl_I_ring' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC2Ev': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC1Ev': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/lib/libginac.a(numeric.o):/usr/local/include/cln/object.h:216: more undefined references to `cln::cl_free_heap_object(cln::cl_heap*)' follow /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC2Ei': /usr/local/include/cln/integer_class.h:52: undefined reference to `cln::cl_I_constructor_from_L(long)' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC2Ei': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC1Ei': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC1Ei': /usr/local/include/cln/integer_class.h:52: undefined reference to `cln::cl_I_constructor_from_L(long)' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC1Ei': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' /usr/local/lib/libginac.a(numeric.o): In function `_ZN5GiNaC7numericC2Ej': /usr/local/include/cln/object.h:216: undefined reference to `cln::cl_free_heap_object(cln::cl_heap*)' and thats just the start of it. Does anyone know what is causing this. Please help! Thanks, Lane.