-export OPENWRTVERSION
-export IS_TTY=$(shell tty -s && echo 1 || echo 0)
-export LD_LIBRARY_PATH:=$(if $(LD_LIBRARY_PATH),$(LD_LIBRARY_PATH):)$(STAGING_DIR_HOST)/lib
-export DYLD_LIBRARY_PATH:=$(if $(DYLD_LIBRARY_PATH),$(DYLD_LIBRARY_PATH):)$(STAGING_DIR_HOST)/lib
+export SOURCE_DATE_EPOCH
+export GIT_CONFIG_PARAMETERS='core.autocrlf=false'
+export GIT_ASKPASS:=/bin/true
+export MAKE_JOBSERVER=$(filter --jobserver%,$(MAKEFLAGS))
+export GNU_HOST_NAME:=$(shell $(TOPDIR)/scripts/config.guess)
+export HOST_OS:=$(shell uname)
+export HOST_ARCH:=$(shell uname -m)
+
+# prevent perforce from messing with the patch utility
+unexport P4PORT P4USER P4CONFIG P4CLIENT
+
+# prevent user defaults for quilt from interfering
+unexport QUILT_PATCHES QUILT_PATCH_OPTS
+
+unexport C_INCLUDE_PATH CROSS_COMPILE ARCH
+
+# prevent distro default LPATH from interfering
+unexport LPATH