Re: [Help-glpk] Linking errors when using cfg.h in a MacOs X

[Heinrich Schuchardt]

Hello Jose,

when I ran
nm -g /usr/local/lib/libglpk.so | grep graph
on Linux it showed that cfg_build_graph is not an exported symbol.

cfg_build_graph is not a function described in doc/glpk.pdf, and is not 
meant to be used by an external program.

>>>> The code compiles perfectly in a Linux machine.
Your example does not compile on my Linux system:
~/temp$ g++ -m64 -g main1.cpp -o main1 
-I/home/user/src/glpk-4.54/src/cglib 
-I/home/user/src/glpk-4.54/src/misc/ -I/home/user/src/glpk-4.54/src/env/ 
-I/home/user/src/glpk-4.54/src/ -lglpk
/tmp/cceieEVB.o: In function `main':
/home/user/temp/main1.cpp:17: undefined reference to `_glp_cfg_build_graph'
collect2: error: ld returned 1 exit status

So I wonder how you made you program compile on your Linux machine. Did 
you manipulate the list of exported symbols?

Best regards

Heinrich

On 18.06.2014 07:26, Jose Walteros wrote:
> Dear Heinrich,
>
> Thank you for your early response. I just checked the paths and the version and 
> it is 4.54, which is the one I am actually using.
>
> The same goes for the path to /src/cglib, It points to the 4.54.
>
> Is there anything else that might be happening?
>
> Thanks
>
> > On Jun 17, 2014, at 11:50 PM, "Heinrich Schuchardt" <address@hidden> wrote:
> >
> > Hello Jose,
> >
> > The errors you report look like you are linking to an old version of GLPK which 
> > does not contain the library function you want to use,
> >
> > You could check the output of glp_version.
> >
> > You can influence the library loadpath on OS X by exporting DYLD_LIBRARY_PATH.
> >
> >
> > Best regards
> >
> > Heinrich Schuchardt
> >
> > http://www.xypron.de
> >
> >
> >
> > Jose L Walteros <address@hidden> schrieb:
> > > Hi all,
> > >
> > > I tried to send this before and I think it didn't work. I am sorry if you 
> > > receive it again.
> > >
> > > I have been working on a code for a while that uses the conflict graph 
> > > libraries of GLPK. The code compiles perfectly in a Linux machine. However, 
> > > when I try to compile it on a MacOS X (via the console) I get some linking 
> > > errors.
> > >
> > > To give you an idea of my problem, I attached bellow a makefile and two trivial 
> > > applications: main1.cpp is an application that reads clique4.lp, generates the 
> > > conflict graph, and prints the number of vertices of such graph. As I 
> > > mentioned, the code compiles perfectly in Linux using the same makefile (after 
> > > updating the corresponding paths). In MacOS X, I get the following error:
> > >
> > > -----------------------------------------
> > > Undefined symbols for architecture x86_64:
> > >    "__glp_cfg_build_graph", referenced from:
> > >        _main in main1-5183c5.o
> > > ld: symbol(s) not found for architecture x86_64
> > > clang: error: linker command failed with exit code 1 (use -v to see invocation)
> > > make: *** [main1] Error 1
> > > -----------------------------------------
> > >
> > > To make sure there was no issues with the installation of GLPK or the path to 
> > > the libraries, I created main2.cpp, which is an applications that simply reads 
> > > and solves clique4.lp. Contrary to the previous case, main2.cpp compiles and 
> > > runs perfectly.
> > >
> > > I have tried many things, but I haven't been able to make it work. I hope you 
> > > guys can help.
> > >
> > > Regards,
> > >
> > > Attachments:
> > >
> > > -----------------------------------------
> > > main1.cpp
> > > -----------------------------------------
> > > #include <iostream>
> > > extern "C" {
> > >         #include <glpk.h>
> > >         #include "cfg.h"
> > >      #include "env.h"
> > >      #include "prob.h"
> > > }
> > >
> > > int main(int argc, const char * argv[])
> > > {
> > >      glp_prob *P;
> > >         CFG *G;
> > >         int nV, v, u, degree;
> > >
> > >      P = glp_create_prob();
> > >         glp_read_lp(P, NULL, "./clique4.lp");
> > >         G = cfg_build_graph(P);
> > >
> > >         nV = G->nv;
> > >
> > >         std::cout<<"# vertices: "<<nV<<std::endl;
> > >
> > >         int *ref = G->ref;
> > >         int *neg = G->neg;
> > >         int *pos = G->pos;
> > >
> > >         for (v = 1; v <= nV; v++){
> > > std::cout<<"vertex "<<v<<" --> variable "<<ref[v]<<"\n";
> > > std::cout<<" pos "<<pos[ref[v]]<<" neg "<<neg[ref[v]]<<"\n";
> > >         }
> > >
> > >      return 0;
> > > }
> > > -----------------------------------------
> > > main2.cpp
> > > -----------------------------------------
> > >
> > > #include <iostream>
> > > extern "C" {
> > >         #include <glpk.h>
> > > }
> > >
> > > int main(int argc, const char * argv[])
> > > {
> > >      glp_prob *P;
> > >
> > >      P = glp_create_prob();
> > >         glp_read_lp(P, NULL, "./clique4.lp");
> > >      glp_simplex(P, NULL);
> > >
> > >      return 0;
> > > }
> > > -----------------------------------------
> > > Makefile
> > > -----------------------------------------
> > >
> > > CPP          = g++
> > > ARGS         = -m64 -g
> > > GLPKPATH     = /Users/jwalteros/Applications/GLPK/glpk-4.54
> > > GLPKLIBPATH  = /usr/local
> > > GLPK         = $(GLPKLIBPATH)/include/
> > > GLPKSRC      = $(GLPKPATH)/src/
> > > GLPKCGLIB    = $(GLPKPATH)/src/cglib/
> > > GLPKENV      = $(GLPKPATH)/src/env/
> > > GLPKMISC     = $(GLPKPATH)/src/misc/
> > > LIBGLPK      = $(GLPKLIBPATH)/lib/
> > >
> > > all: main1 main2
> > >
> > > main1:
> > >         $(CPP) $(ARGS) -o main1 main1.cpp -I$(GLPK) -I$(GLPKSRC) -I$(GLPKCGLIB) 
> > > \
> > >         -I$(GLPKENV) -I$(GLPKENV) -I$(GLPKMISC) -L$(LIBGLPK) -lglpk
> > >
> > > main2:
> > >         $(CPP) $(ARGS) -o main2 main2.cpp -I$(GLPK) -L$(LIBGLPK) -lglpk
> > >
> > > -----------------------------------------
> > > _______________________________________________ Help-glpk mailing list 
> > > address@hidden https://lists.gnu.org/mailman/listinfo/help-glpk