Source: scheme48 Version: 1.9-5 The HTML documentation shipped in scheme48-doc is generated from TeX sources using the tex2page program: https://ds26gte.github.io/tex2page/ However, tex2page isn't listed as a build dependency, indeed it doesn't even appear to be packaged for debian; the Debian package simply ships pregenerated HTML files from the tarball. If the HTML docs appear out of date (based on file mtimes), make will try to invoke tex2page during the package build, causing a FTBFS. This can happen when building sources cloned from git://anonscm.debian.org/collab-maint/scheme48.git The solution is to package tex2page in Debian, and make sure it is always invoked to build the HTML files from source when the package is being built.
