when i am trying to compile given source it gives linker error :
tutorial4.o:(.rodata._ZTIN5clang13MyASTConsumerE[typeinfo for clang::MyASTConsumer]+0x10): undefined reference to `typeinfo for clang::ASTConsumer’
collect2: ld returned 1 exit status
make: *** [tutorial4] Error 1
Source code is: all necessary header files are included and there is no syntax error in this source code, required libraries are also specified in make file.