Question

I’m learning c++ and I’m trying to use a library that I’ve downloaded from internet in my program ( from here https://mattmccutchen.net/bigint/).
Because I want everything to be quite tidy, I put all the .hh files in a subfolder named “BI”.
However when I try to compile my .cpp file with g++ (It’s MinGW on Windows XP SP3), the compiler outputs the following error:


J:\comp proj\FS>J:\Programmi\MinGW\bin\g++.exe "J:\comp proj\FS\test.cpp" -o "J:\comp proj\FS\test.exe" -I "J:\comp proj\FS\BI"
E:\DOCUME~1\MrJackV\IMPOST~1\Temp\ccidH1Z6.o:test.cpp:(.text+0x2c): undefined reference to BigInteger::BigInteger(int)'
E:\DOCUME~1\MrJackV\IMPOST~1\Temp\ccidH1Z6.o:test.cpp:(.text+0x11b): undefined reference tooperator<<(std::ostream&, BigInteger const&)'
E:\DOCUME~1\MrJackV\IMPOST~1\Temp\ccidH1Z6.o:test.cpp:(.text$ZNK10BigIntegermlERKS[BigInteger::operator*(BigInteger const&) const]+0x29): undefined reference
to `BigInteger::multiply(BigInteger const&, BigInteger const&)'
collect2: ld returned 1 exit status


I’ve tried using the -I, -l and -L switches to fix the problem but with no success.
Moreover I’ve tried in the cpp to put #include "BI/BigIntegerLibrary.hh" but that didn’t work.

Is there something I’m doing wrong?

Thanks in advance.

Answer 1

Ok, so after some messing around I figured out that I needed to do a couple of things

1. add the -L switch with the dir of the header files
2. add to the g++ command line all the .cc files (e.g. g++ test.cpp BigInteger.cc etc.)
3. put everything in a batch file for semplicity

wow, now it seems quite easy!