Experimental Physics and
Industrial Control System

"Wang Xiaoqiang" <[email protected]> · Wed, 6 May 2009 14:12:13 +0200

Hi,

On windows, with cygwin-x86 and win32-x86 host arch, I have compiled
EPICS base 
to create shared libraries.

Then I setup a simple application to create a DLL, and it complains
undefined reference (error output below).
I understand that this is because epicsShareExtern is defined as
__declspec(dllimport).
Linker is instructed to call these functions in some DLLs which is not
true, since I
also compiled these functions in.
On the other hand, it builds successfully using the Makefile.support,
which separates
the actual functions to a DLL, to satisfy the linker. That looks a bit
awkward. 

Because of my limited knowledge, I would ask gurus, are there other
solutions to 
such a pecular situation. Actually asyn/testManager example has a
similar problem, 
which wants to creat a single EXE.

Thanks in advance.

==== here starts the make output for cygwin-x86 ===
make -C O.cygwin-x86 -f ../Makefile TOP=../../.. T_A=cygwin-x86 install
make[1]: Entering directory `/w/test/epicsdum/dumApp/src/O.cygwin-x86'
g++ -o dum.dll -shared -Wl,--out-implib,dum.lib
-L/usr/local/epics/base/lib/cygwin-x86
dum_registerRecordDeviceDriver.o dumHello.o    -lrecIoc -lsoftDevIoc
-lmiscIoc -lrsrvIoc -ldbtoolsIoc -lasIoc -ldbIoc -lregistryIoc
-ldbStaticIoc -lca -lCom  -lpthread   -lreadline -lcurses -lm
dum_registerRecordDeviceDriver.o:dum_registerRecordDeviceDriver.cpp:(.te
xt+0x7): undefined reference to `__imp__pvar_func_helloRegister'
dum_registerRecordDeviceDriver.o:dum_registerRecordDeviceDriver.cpp:(.te
xt+0x37): undefined reference to `__imp__pvar_func_helloRegister'
dum_registerRecordDeviceDriver.o:dum_registerRecordDeviceDriver.cpp:(.te
xt+0x58): undefined reference to `__imp__pvar_int_helloVariable'
Creating library file: dum.lib
collect2: ld returned 1 exit status
make[1]: *** [dum.dll] Error 1
make[1]: Leaving directory `/w/test/epicsdum/dumApp/src/O.cygwin-x86'

--
Dr. Xiaoqiang Wang
Paul Scherrer Institut, WBGB/010
5232 Villigen PSI, Switzerland

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System