Re: [igraph] Help with MAKE error

[Tamas Nepusz]

Hi,

> I am trying to MAKE igraph 0.5.3
The error you are seeing is a known bug with Cygwin if you are building
igraph without GMP support, see here:

https://bugs.launchpad.net/igraph/+bug/380622

You have two choices:

1. Install the GMP packages in Cygwin, reconfigure with ./configure and
then run make again.

2. Modify the igraph source code a little bit so it compiles on Cygwin.
You have to add the following lines to src/igraph_math.h, right before
the line containing the declaration of igraph_fmin:

long double igraph_fabsl(long double a);
#define fabsl(a) igraph_fabsl(a)

You also need to add this to src/math.c before the line containing
"double igraph_fmin":

long double igraph_fabsl(long double a) {
  if (a<0) {
    return -a;
  } else {
    return a;
  }
} 

-- 
Tamas