[LyX/master] Fix compatibility issue with 64-bit cygwin.

[Enrico Forestieri]

commit b3735501c7952ec53600f94d90ae8e164300ca76
Author: Enrico Forestieri <for...@lyx.org>
Date:   Fri Jul 11 16:49:10 2014 +0200

    Fix compatibility issue with 64-bit cygwin.

diff --git a/src/support/os_cygwin.cpp b/src/support/os_cygwin.cpp
index e0c0bd1..572273c 100644
--- a/src/support/os_cygwin.cpp
+++ b/src/support/os_cygwin.cpp
@@ -449,7 +449,7 @@ bool autoOpenFile(string const & filename, auto_open_mode 
const mode,
        // reference: http://msdn.microsoft.com/en-us/library/bb762153.aspx
        string const win_path = to_local8bit(from_utf8(convert_path(filename, 
PathStyle(windows))));
        char const * action = (mode == VIEW) ? "open" : "edit";
-       bool success = reinterpret_cast<int>(ShellExecute(NULL, action,
+       bool success = reinterpret_cast<long>(ShellExecute(NULL, action,
                                        win_path.c_str(), NULL, NULL, 1)) > 32;
 
        if (!path.empty() && !lyxrc.texinputs_prefix.empty()) {