Alpha specific bugs are marked in the bug tracking system using the "usertags" mechanism (http://lists.debian.org/debian-devel-announce/2005/09/msg00002.html) with user debian-alpha@lists.debian.org. The tags are:

The result can be seen here: http://bugs.debian.org/cgi-bin/pkgreport.cgi?tag=ftbfs,broken,buggy,maybe,hardware;users=debian-alpha@lists.debian.org

debian-installer bugs are not tagged, since they can be found at http://bugs.debian.org/cgi-bin/pkgreport.cgi?maint=debian-boot@lists.debian.org;include=alpha.

Also not tagged are the bugs of the following Alpha-specific packages:

FTBFS can be checked at http://buildd.debian.org/~jeroen/status/architecture.php?a=alpha