Freetype2 64bit on OmniOS

Question

I'm installing freetype2 from source on a 64 bit version of OmniOS. I need to install 64-bit freetype2.

The problem is I'm getting a compilation error I can't figure out.

I've tried using the built in package manager's freetype, but all available versions are 32 bit.

wget -O freetype-2.9.1.tar.gz https://sourceforge.net/projects/freetype/files/freetype2/2.9.1/freetype-2.9.1.tar.gz/download
tar -xvf freetype-2.9.1.tar.gz
cd freetype-2.9.1
./configure CC="gcc -m64" --prefix=/usr/local/src/freetype-2.9.1 > configure.out 2>&1
gmake > compile.out 2>&1

The configure works just fine, but when I compile with gmake I get:

builds/unix/ftsystem.c:19:10: fatal error: ft2build.h: No such file or directory

#include <ft2build.h>
compilation terminated.
gmake: *** [/usr/local/src/freetype-2.9.1/builds/freetype.mk:210: /usr/local/src/freetype-2.9.1/objs/ftsystem.lo] Error 1