-# Default FLAGS, (can be overridden by user such as "make CFLAGS=-O2")
-WARN_FLAGS=-Wall -Wextra -Wmissing-declarations -Wwrite-strings -Wswitch-enum
-CFLAGS=-O2
-
-# Additional flags that we will append to whatever the user set.
-# These aren't intended for the user to manipulate.
-extra_cflags := $(shell pkg-config --cflags glib-2.0 gmime-2.4 talloc)
-extra_cxxflags := $(shell xapian-config --cxxflags)
-
-emacs_lispdir := $(shell pkg-config emacs --variable sitepkglispdir)
-# Hard-code if this system doesn't have an emacs.pc file
-ifeq ($(emacs_lispdir),)
- emacs_lispdir = $(prefix)/share/emacs/site-lisp
-endif
+WARN_CXXFLAGS=-Wall -Wextra -Wwrite-strings -Wswitch-enum
+WARN_CFLAGS=$(WARN_CXXFLAGS) -Wmissing-declarations
+
+# Additional programs that are used during the compilation process.
+EMACS ?= emacs
+# Lowercase to avoid clash with GZIP environment variable for passing
+# arguments to gzip.
+gzip = gzip
+
+bash_completion_dir = /etc/bash_completion.d
+zsh_completion_dir = /usr/share/zsh/functions/Completion/Unix