[igraph] build error on Windows

[胡啸天]

Hi,

 I meet a error when building the igraph 7.0.1 by MS VS 2012, the error is following:

1>e:\program_lib\python\igraph\igraph-0.7.1-msvc\igraph-0.7.1-msvc\src\prpack.cpp(66): error C2146: syntax error : missing ';' before identifier 'prpack_graph'

1>e:\program_lib\python\igraph\igraph-0.7.1-msvc\igraph-0.7.1-msvc\src\prpack.cpp(66): error C3861: 'prpack_graph': identifier not found

1>e:\program_lib\python\igraph\igraph-0.7.1-msvc\igraph-0.7.1-msvc\src\prpack.cpp(67): error C2065: 'prpack_graph' : undeclared identifier

can you tell me what happened and how to solve this problem? 

Thanks!

Timothy Hu