Running "emacs -Q etc/compilation.txt" and scrolling down to the perl section shows none of the sample perl errors matched at all, where I hoped they would be. I think the "^" anchor added by compilation-mode-font-lock-keywords means perl and some other more obscure patterns need a ".*", like they had back in Emacs 21, to work in the middle of a line. I noticed this on the perl one. I thought it was working fine not so long ago, so I don't know what/when/how it went bad. (The looseness of Emacs 22 not anchoring reverted, but the patterns not put back at the same time too??) 2009-07-25 Kevin Ryde * progmodes/compile.el (compilation-error-regexp-alist-alist): In aix, ftnchek, mips-1, mips-2, perl, sun, 4bsd entries add ".*" so as to match in the middle of a line, now that there's a "^" anchor is again enforced by compilation-mode-font-lock-keywords. These patterns were otherwise failing to match anything at all. In the 4bsd entry remove the "^" from inside the \\(\\) grouping since it's now unnecessary and since inside a group it isn't recognised by the omake indentation hack in compilation-mode-font-lock-keywords (meaning it wouldn't work with indentation).