[LLVMbugs] [Bug 20854] New: Template instantiation fails with undefined reference

[bugzilla-daemon at llvm.org]

http://llvm.org/bugs/show_bug.cgi?id=20854

            Bug ID: 20854
           Summary: Template instantiation fails with undefined reference
           Product: clang
           Version: trunk
          Hardware: PC
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P
         Component: C++
          Assignee: unassignedclangbugs at nondot.org
          Reporter: wpoely86 at gmail.com
                CC: dgregor at apple.com, llvmbugs at cs.uiuc.edu
    Classification: Unclassified

Created attachment 12992
  --> http://llvm.org/bugs/attachment.cgi?id=12992&action=edit
The example that fails

I've make a small piece of code (see attachment) that compiles fine with GCC
4.9.1 and icpc-2015.0.090 but not with Clang-3.5.

I've split up the definition and declaration of a template class in the usual
way: in the cpp file, all templates used have been explicitly Instantiation.
If you put everything in the header, everything works fine.

Clang fails with undefined reference to the template class. If I look at the
symbols in the object file generated by Clang and GCC:
GCC:
0000000000000000 W BlockStructure<Matrix>::BlockStructure(int)
0000000000000000 W BlockStructure<Matrix>::BlockStructure(int)
0000000000000000 n _ZN14BlockStructureI6MatrixEC5Ei
0000000000000000 W BlockStructure<Matrix>::~BlockStructure()
0000000000000000 W BlockStructure<Matrix>::~BlockStructure()
0000000000000000 W BlockStructure<Matrix>::~BlockStructure()
0000000000000000 n _ZN14BlockStructureI6MatrixED5Ev
0000000000000000 V typeinfo for BlockStructure<Matrix>
0000000000000000 V typeinfo name for BlockStructure<Matrix>
0000000000000000 V vtable for BlockStructure<Matrix>
                 U vtable for __cxxabiv1::__class_type_info
                 U operator delete(void*)

Clang:
0000000000000000 r GCC_except_table1
                 U _Unwind_Resume
0000000000000000 W BlockStructure<Matrix>::~BlockStructure()
0000000000000000 W BlockStructure<Matrix>::~BlockStructure()
0000000000000000 V typeinfo for BlockStructure<Matrix>
0000000000000000 V typeinfo name for BlockStructure<Matrix>
0000000000000000 V vtable for BlockStructure<Matrix>
                 U vtable for __cxxabiv1::__class_type_info
                 U operator delete(void*)
                 U __gxx_personality_v0

It seems like Clang skips the instantiation of the templates with expecting of
the destructor?

-- 
You are receiving this mail because:
You are on the CC list for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-bugs/attachments/20140905/95afc901/attachment.html>