private/cord_pos.h missing from package

/usr/include/gc/cord.h refers to an additional header file, private/cord_pos.h. This is missing from the distribution, which makes that feature of the library unusable.

Test program:

---snip---
#include <gc/cord.h>
int main() { return 0; }
---snip---

Compile with:

gcc test.c

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: libgc-dev 1:7.2d-5ubuntu2
ProcVersionSignature: Ubuntu 3.11.0-26.45-generic 3.11.10.12
Uname: Linux 3.11.0-26-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: amd64
Date: Sat Sep 6 15:02:58 2014
Dependencies:
 gcc-4.9-base 4.9.1-4ubuntu3 [origin: unknown]
 libc6 2.17-93ubuntu4
 libgc1c2 1:7.2d-5ubuntu2
 libgcc1 1:4.9.1-4ubuntu3 [origin: unknown]
 multiarch-support 2.17-93ubuntu4
InstallationDate: Installed on 2014-08-02 (34 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MarkForUpload: True
SourcePackage: libgc
UpgradeStatus: No upgrade log present (probably fresh install)