using g++, undefined reference to `llvm::Module::dump() const'

Question

Hi I'm compiling the following program:

#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IRReader/IRReader.h"
#include "llvm/Support/SourceMgr.h"

#include <cstdlib>
#include <string>

using namespace llvm;


int main(int argc, char **argv)
{
    std::string target = "'./self_tests/src_huawei/alg5.cpp'";
    std::string cml = "clang -emit-llvm -c " + target + " -o 'result.bc' -O3 -fno-vectorize -fno-slp-vectorize -fno-unroll-loops";

    int result = system(cml.c_str());
    
    LLVMContext CurrContext;
    SMDiagnostic Err;
    std::unique_ptr<Module> mod = parseIRFile(llvm::StringRef("result.bc"), Err, CurrContext);

    mod->dump();
    
    return 0;
}

and the g++ compiler reported an error of undefined reference to 'llvm::Module::dump() const'

The command line is as follow:

g++ -m64 -g -lLLVM -lLLVMSupport -lLLVMDemangle -lLLVMDemangle ./src/test.cpp -o test.out

I included all the library have "llvm" in there name, but still not work.

Answer 1

LLVM considers dump functions/functionality as optional, only for debugging and should not be expected. Instead you can use print

void Module::print(raw_ostream &OS,
    AssemblyAnnotationWriter *AAW,
    bool ShouldPreserveUseListOrder = false,
    bool IsForDebug = false 
)   

For example:

mod->print(llvm::errs(), nullptr);