diff -urN Python-2.7.10.orig/Modules/getpath.c Python-2.7.10/Modules/getpath.c
--- Python-2.7.10.orig/Modules/getpath.c	2015-07-07 12:58:16.162926800 +0100
+++ Python-2.7.10/Modules/getpath.c	2015-07-07 13:09:22.496926800 +0100
@@ -10,6 +10,10 @@
 #include <mach-o/dyld.h>
 #endif
 
+#ifdef __CYGWIN__
+#include <sys/cygwin.h>
+#endif
+
 /* Search in some common locations for the associated Python libraries.
  *
  * Two directories must be found, the platform independent directory
@@ -229,8 +233,21 @@
 static void
 copy_absolute(char *path, char *p)
 {
+#if defined(__CYGWIN__)
+    int win_drive = (p[0] != '\0' && p[1] == ':') ? 1 : 0;
+    if (p[0] == SEP || win_drive)
+#else
     if (p[0] == SEP)
+#endif
         strcpy(path, p);
+#if defined(__CYGWIN__)
+        /* Turn absolute paths with Windows drive letters into their
+           Cygwin equivalent since sys.path can't have drive seps (:)
+           in since those delimit path list entries */
+        if (win_drive) {
+            cygwin_conv_path(CCP_WIN_A_TO_POSIX, p, path, MAXPATHLEN + 1);
+        }
+#endif
     else {
         if (!getcwd(path, MAXPATHLEN)) {
             /* unable to get the current directory */
@@ -482,7 +499,11 @@
         }
         else
                 progpath[0] = '\0';
+#if defined(__MSYS__)
+        if (progpath[0] != SEP && progpath[0] != '\0' && progpath[1] != ':')
+#else
         if (progpath[0] != SEP && progpath[0] != '\0')
+#endif
                 absolutize(progpath);
         strncpy(argv0_path, progpath, MAXPATHLEN);
         argv0_path[MAXPATHLEN] = '\0';