+################################################################################
+
+# Directory used by GHC (and possibly other tools) for storing
+# temporary files. If your /tmp isn't big enough, either override
+# this in build.mk or set your environment variable "TMPDIR" to point
+# to somewhere with more space. (TMPDIR=. is a good choice).
+
+# DEFAULT_TMPDIR isn't called TMPDIR because GNU make tends to
+# override an environment variable with the value of the make variable
+# of the same name (if it exists) when executing sub-processes, so
+# setting the TMPDIR env var would have no effect in the build tree.