autotrace-0.31.1 fails with --as-needed in LDFLAGS. I have created a patch for the issue.
Created attachment 91843 [details, diff] patch for when --as-needed is used This patch adds libpng and ImageMagick libraries to the Automake instruction building the autotrace library.
I have sent an e-mail to the upstream maintainer listed at the bottom of http://autotrace.sourceforge.net/index.html with the patch as well.
This seems to be fixed in 0.31.1-r2 for some time now: *autotrace-0.31.1-r2 (20 Jan 2007) 20 Jan 2007; Mike Frysinger <vapier@gentoo.org> +files/autotrace-0.31.1-libs.patch, +autotrace-0.31.1-r2.ebuild: Cleanup ebuild, add support for USE=pdf, and fix linking of libautotrace.