llc undefined symbol

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#1

Hi all

I’m writing a pass for the llc tool. If I try to load my pass(llc -load …/mypass.so), this error message appears :

Error opening ‘/nfs/wsi/ti/graumann/llvm-2.5/Release/lib/LLVMMicha.so’: /nfs/wsi/ti/graumann/llvm-2.5/Release/lib/LLVMMicha.so: undefined symbol: _ZTVN12_GLOBAL__N_119MyRegisterAllocatorE

-load request ignored.

Is this code wrong for the pass registration, or the makefile?

Thank you for help

Michael

Code of my pass:

using namespace llvm;

namespace {

struct MyRegisterAllocator : public MachineFunctionPass {

static char ID; // Pass identification, replacement for typeid

MyRegisterAllocator() : MachineFunctionPass(&ID) {}

virtual bool runOnMachineFunction(MachineFunction &MF);

};

char MyRegisterAllocator::ID = 0;

}

static RegisterPassX(“myregalloc”,

" my register allocator help string");

FunctionPass* createMyRegisterAllocator() {

return new MyRegisterAllocator();

}

static RegisterRegAlloc MyRegAlloc(“myregalloc”,

" my register allocator help string",

createMyRegisterAllocator);

the makefile:

LEVEL = …/…/…

LIBRARYNAME = LLVMMicha

LOADABLE_MODULE = 1

USEDLIBS =

#LLVMLIBS = LLVMCore.a LLVMSupport.a LLVMSystem.a

LINK_COMPONENTS = support system

include $(LEVEL)/Makefile.common

#2

You have to define (instantiate) all your virtual functions. runOnMachineFunction is one such function, there may be others as well.

#3

Hi
At the moment there are in my pass only this virtual function
(runOnMachineFunction). maybe is there an other reason?

Thank you
Michael

#4

Again, best guess since you don't actually include enough information...

You do not have a definition for it. The anonymous namespace of the header doesn't create a single anonymous namespace for the header, rather, it uses the anonymous namespace of the translation unit. Each use of the header creates a different class, completely unrelated to all other classes of the exact same name. Try never defining classes in anonymous namespaces in headers.