I caught this on Gentoo Prefix: checking expat.h usability... no checking expat.h presence... yes configure: WARNING: expat.h: present but cannot be compiled configure: WARNING: expat.h: check for missing prerequisite headers? configure: WARNING: expat.h: see the Autoconf documentation configure: WARNING: expat.h: section "Present But Cannot Be Compiled" configure: WARNING: expat.h: proceeding with the compiler's result configure: WARNING: ## ----------------------------------------------------------- ## configure: WARNING: ## Report this to avahi (at) lists (dot) freedesktop (dot) org ## configure: WARNING: ## ----------------------------------------------------------- ## checking for expat.h... no checking for XML_ParserCreate in -lbsdxml... no configure: error: *** neither libexpat not libbsdxml could be found *** We need a dependency on dev-libs/expat.
My apologies for the noise. I didn't look at this carefully enough. The dependency is there.