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Link Error with STEPControl_Reader in importexport sample

Yang Jianxin's picture

I try to compile the importexport sample coming with OpenCASCADE 6.5 using Visual
Studio 2010 with Qt 4.8.0, however i met following link errors:

Translate.obj : error LNK2019: unresolved external symbol "public: unsigned int
__thiscall STEPControl_Reader::TransferRoot(int)" (?TransferRoot@STEPControl_Rea
der@@QAEIH@Z) referenced in function "private: class Handle_TopTools_HSequenceOf
Shape __thiscall Translate::importSTEP(class QString const &)" (?importSTEP@Tran
Translate.obj : error LNK2019: unresolved external symbol "public: virtual int _
_thiscall STEPControl_Reader::NbRootsForTransfer(void)" (?NbRootsForTransfer@STE
PControl_Reader@@UAEHXZ) referenced in function "private: class Handle_TopTools_
HSequenceOfShape __thiscall Translate::importSTEP(class QString const &)" (?impo

I have checked the link libraries, "-lTKStep -lTKSTEP209 -lTKSTEPAttr -lTKSTEPBase -lTKXSBase" are in the list. I also add all OCC libraries to the list, however
the error remains. I switch the STEPControl_Reader to IGESControl_Reader, there
is no such problem. Would you please give the suggestions? Thanks.

Yang Jianxin's picture

I found the problem, it is a bug of Qt.
In the IESample.pro, it defines "-lTKStep -lTKSTEP209 -lTKSTEPAttr -lTKSTEPBase -lTKXSBase", however the
generated Makefile contains two "-lTKSTEP209.lib", i have to change one into "-lTKStep.lib", thus it works.

coustet's picture

A workaround is to use QMAKE_LFLAGS += @liblist.txt, with all the lib names in liblist.txt.
See the documentation for "LINK Command Files" in MSDN.

Benjamin Bihler's picture

Another workaround can be to specify the library including the .lib file extension for Windows systems like this:

win32:LIBS += $$quote($${QMAKE_LIBDIR}/TKStep.lib)

This works great for me.

P Dolbey's picture

Not so much a bug as a "feature" - when you specify a lib like -lTKStep, qmake searches for the "latest" version of that lib by checking for a numeric version suffix on the libname and uses that in the makefile. In this case that method thinks its found version "209".