diff --git a/Makefile b/Makefile
index 7a66897cc2..bcbe9fc10c 100644
--- a/Makefile
+++ b/Makefile
@@ -165,6 +165,9 @@ HOSTNM:=$(shell which $(HOSTNM) || type -p $(HOSTNM) || echo nm)
 export HOSTAR HOSTAS HOSTCC HOSTCXX HOSTFC HOSTLD
 export HOSTCC_NOCCACHE HOSTCXX_NOCCACHE
 
+# Make sure pkg-config doesn't look outside the buildroot tree
+unexport PKG_CONFIG_PATH
+
 # bash prints the name of the directory on 'cd <dir>' if CDPATH is
 # set, so unset it here to not cause problems. Notice that the export
 # line doesn't affect the environment of $(shell ..) calls, so