diff --git a/recipes/treebest/build.sh b/recipes/treebest/build.sh
index 8c92e6753199c..2dcd77421b91a 100644
--- a/recipes/treebest/build.sh
+++ b/recipes/treebest/build.sh
@@ -1,6 +1,9 @@
 #!/bin/sh
 set -e
 
+# https://github.com/conda-forge/bison-feedstock/issues/7
+export M4="${PREFIX}/bin/m4"
+
 make
 mkdir -p "$PREFIX/bin"
 cp treebest "$PREFIX/bin/"