--- tests/Makefile.am.orig	2021-03-08 17:51:22 UTC
+++ tests/Makefile.am
@@ -129,9 +129,9 @@ tnfd_SOURCES=tnfd.cc
 # This is the name of a directory which will be used for newform
 # input/output in the "make check" tests and removed afterwards.
 
-export NF_DIR:=nftmp
-export SNF_DIR:=snftmp
-export TCURVE_DIR:=tcurves
+export NF_DIR=nftmp
+export SNF_DIR=snftmp
+export TCURVE_DIR=tcurves
 
 check_g0n: g0n_tests
 	@echo Running g0n checks...