Link problems


I am trying to build an EXE that links with some own build shared libararies on linux (suse 91). I now get unresolved externals on everything I use of my own shared libraries. Any ideas of options I can test

Some output:

pgCC -O3 -g -D_REENTRANT -DACE_HAS_AIO_CALLS -I/home/build/ACE/PG/ACE_wrappers -DACE_HAS_EXCEPTIONS -DACE_NO_INLINE -I…/…/… -I…/…/…/Kokyu -c -o .obj/MIF.o MIF.cpp
pgCC -O3 -g -D_REENTRANT -DACE_HAS_AIO_CALLS -I/home/build/ACE/PG/ACE_wrappers -DACE_HAS_EXCEPTIONS -DACE_NO_INLINE -I…/…/… -I…/…/…/Kokyu -L/home/build/ACE/PG/ACE_wrappers/ace -L./ -L…/…/…/lib -o MIF .obj/MIF.o -lKokyu -lACE -ldl -lpthread -lrt
.obj/MIF.o(.text+0x130): In function main': /home/build/ACE/PG/ACE_wrappers/Kokyu/tests/DSRT_MIF/MIF.cpp:130: undefined reference to _Q2_5Kokyu26DSRT_Dispatcher<>::create_DSRT_dispatcher__Q2_5Kokyu54DSRT_Dispatcher_Factory__tm__23_20mif_scheduler_traitsSFRCQ2_5Kokyu15DSRT_ConfigInfo_Q2_3std54auto_ptr__tm(void)’
.obj/MIF.o(.text+0x73b):/home/build/ACE/PG/ACE_wrappers/Kokyu/tests/DSRT_MIF/MIF.cpp:180: undefined reference to Kokyu::DSRT_Dispatcher<mif_scheduler_traits>::shutdown(int (void))' .obj/MIF.o(.text+0xa56): In function MyTask’:
/home/build/ACE/PG/ACE_wrappers/Kokyu/tests/DSRT_MIF/MIF.cpp:60: undefined reference to __pp__41ACE_Atomic_Op__tm__20_16ACE_Thread_MutexlFv_Z2Z' .obj/MIF.o(.text+0xc29): In function svc’:
/home/build/ACE/PG/ACE_wrappers/Kokyu/tests/DSRT_MIF/MIF.cpp:78: undefined reference to schedule__Q2_5Kokyu46DSRT_Dispatcher__tm__23_20mif_scheduler_traitsFQ2_Z1Z6Guid_tRCQ2_Z1Z15QoSDescriptor_t_i' .obj/MIF.o(.text+0xe2f):/home/build/ACE/PG/ACE_wrappers/Kokyu/tests/DSRT_MIF/MIF.cpp:115: undefined reference to cancel_schedule__Q2_5Kokyu46DSRT_Dispatcher__tm__23_20mif_scheduler_traitsFQ2_Z1Z6Guid_t_i’

The full log is online at

Hi Johnny,

Using templates in libraries is a bit tricky since template instantiation occurs at link time. Since your library objects have not been linked, the instantiated object does not exist and is why your getting link errors.

Chapter 11 of the PGI user guide details C++ template instantiation. In particular, section 11.5 gives the steps needed to create libraries that include templates. Although the example uses a static library, the same steps are needed for dynamic libraries.

The basic steps are as follows:

    1. You’ll need to add the flag “–one_instantiation_per_object” to the compilation of each library object.

    1. Next link the objects with the flags “–one_instantiation_per_object --prelink_objects” to instantiate the templates to an object file (located in the “Template.dir” directory).

    1. Finally, create the dynamic library as normal, but include all the Template directory’s object files on the link line.
  • Mat

Ok, I will try this, one thing already. Templates are really standard in C++, a lot of them are used. What I find strange that because I use templates I have to add some compiler options, but also that I can’t use debug builds anymore, this is not real handy.

pgCC --one_instantiation_per_object -O3 -g -D_REENTRANT -DACE_HAS_AIO_CALLS -I/home/build/ACE/PG/ACE_wrappers -DACE_HAS_EXCEPTIONS -DACE_NO_INLINE -I… -DACE_HAS_ACE_TOKEN -DACE_HAS_ACE_SVCCONF -DACE_BUILD_DLL -c -fPIC -o .shobj/Naming_Context.o Naming_Context.cpp
Warning: --one_instantiation and debug not yet supported
PGCC-W-0000-Internal compiler error. read_debug_info: unable to read debug file 0 (Naming_Context.cpp)
pgCC-Fatal-/usr/pgi/linux86-64/5.2/bin/pgcpp2 TERMINATED by signal 11
Arguments to /usr/pgi/linux86-64/5.2/bin/pgcpp2

Ok, I now got further. I use now the following command to build an exe that used the shared libs. No link error, but I can’t find an ACE_Init_Test on disk, I expect it in the current directory, any hints?

pgCC --one_instantiation_per_object --prelink_objects -Wc,-tused -O3 -D_REENTRANT -DACE_HAS_AIO_CALLS -I/home/build/ACE/PG/ACE_wrappers -DACE_NDEBUG -DACE_USE_RCSID=0 -DACE_HAS_EXCEPTIONS -DACE_NO_INLINE -I… -DACE_AS_STATIC_LIBS -c -o .obj/ACE_Init_Test.o ACE_Init_Test.cpp
pgCC --one_instantiation_per_object --prelink_objects -Wc,-tused -O3 -D_REENTRANT -DACE_HAS_AIO_CALLS -I/home/build/ACE/PG/ACE_wrappers -DACE_NDEBUG -DACE_USE_RCSID=0 -DACE_HAS_EXCEPTIONS -DACE_NO_INLINE -I… -DACE_AS_STATIC_LIBS -L/home/build/ACE/PG/ACE_wrappers/ace -L./ -L…/lib -o ACE_Init_Test .obj/Main.o .obj/ACE_Init_Test.o -lTest_Output -lACE -ldl -lpthread -lrt
make[1]: Leaving directory /home/build/ACE/PG/ACE_wrappers/tests' make[1]: Entering directory /home/build/ACE/PG/ACE_wrappers/tests’

You only want to use “–one_instantiation_per_object --prelink_objects” to pre-link the library. You shouldn’t use it when compiling your application since “–prelink_objects” causes pgCC to stop after the prelink step and no executable will be created.

I’ll need to get back to you with the details as to why “-g” doesn’t work with “–one_instantiation” since I don’t know off hand.

  • Mat

Hi Johnny,

The debug problem is a known bug whose fix will appear in a future release.


I did remove the prelink-object but now I get unresolved agains. Seems I have to search a little bit further.