diff --git a/Makefile.am b/Makefile.am
index 9560982..3cbb743 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -38,7 +38,7 @@ TESTS = \
 	tests/encode-neg-index.sh \
 	tests/encode-small.sh
 SH_LOG_COMPILER = /bin/sh
-AM_TESTS_ENVIRONMENT = PATH='$(srcdir)':"$$PATH"; export PATH;
+AM_TESTS_ENVIRONMENT = PATH='$(abs_top_builddir)':"$$PATH"; export PATH;
 TESTS_ENVIRONMENT = $(AM_TESTS_ENVIRONMENT)
 endif
 TEST_EXTENSIONS = .sh