Question

Does anyone have suggestions for how to extend specifically Python 3 with C++? I’ve tried using SWIG but it comes up with a fatal link error when trying to access a library file that doesn’t exist on my computer (Python_d.lib or something similar).

EDIT:

The steps I took were:

1) Downloading swigwin-2.0.4 from http://www.swig.org/download.html

2) Setting up the environment variables (PYTHON_INCLUDE and PYTHON_LIB)

3) Building one of the examples included with the swigwin package. The code for this is posted below. This was built in MVSC++ 2010.

/* File : example.c */

#include "example.h"
#define M_PI 3.14159265358979323846

/* Move the shape to a new location */
void Shape::move(double dx, double dy) {
    x += dx;
    y += dy;
}

int Shape::nshapes = 0;

double Circle::area(void) {
    return M_PI*radius*radius;
}

double Circle::perimeter(void) {
    return 2*M_PI*radius;
}

double Square::area(void) {
    return width*width;
}

double Square::perimeter(void) {
    return 4*width;
}

The relevant part of output I get from this is:

1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\Microsoft.CppBuild.targets(990,5): warning MSB8012: TargetPath(C:\Users\David\Downloads\swigwin-2.0.4\Examples\python\class\.\Debug\example.dll) does not match the Linker's OutputFile property value (C:\Users\David\Downloads\swigwin-2.0.4\Examples\python\class\_example.pyd). This may cause your project to build incorrectly. To correct this, please make sure that $(OutDir), $(TargetName) and $(TargetExt) property values match the value specified in %(Link.OutputFile).

1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\Microsoft.CppBuild.targets(991,5): warning MSB8012: TargetExt(.dll) does not match the Linker's OutputFile property value (.pyd). This may cause your project to build incorrectly. To correct this, please make sure that $(OutDir), $(TargetName) and $(TargetExt) property values match the value specified in %(Link.OutputFile).

1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\Microsoft.CppBuild.targets(992,5): warning MSB8012: TargetName(example) does not match the Linker's OutputFile property value (_example). This may cause your project to build incorrectly. To correct this, please make sure that $(OutDir), $(TargetName) and $(TargetExt) property values match the value specified in %(Link.OutputFile).

1>LINK : fatal error LNK1104: cannot open file 'python32_d.lib'
1>
1>Build FAILED.
1>
1>Time Elapsed 00:00:04.27

Answer 1

Change the build configuration from Debug to Release in MSVC, or check the answers to this question.