diff --git a/7.2/alpine3.8/cli/Dockerfile b/7.2/alpine3.8/cli/Dockerfile
index 0442f0e70c..e67b38c133 100644
--- a/7.2/alpine3.8/cli/Dockerfile
+++ b/7.2/alpine3.8/cli/Dockerfile
@@ -38,6 +38,7 @@ RUN set -x \
 # http://git.alpinelinux.org/cgit/aports/tree/main/nginx-initscripts/nginx-initscripts.pre-install?h=v3.3.2
 
 ENV PHP_INI_DIR /usr/local/etc/php
+ENV PHP_EXTENSION_DIR /usr/local/lib/php/extensions
 RUN mkdir -p $PHP_INI_DIR/conf.d
 
 ##<autogenerated>##
@@ -111,7 +112,8 @@ RUN set -xe \
 	&& docker-php-source extract \
 	&& cd /usr/src/php \
 	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
-	&& ./configure \
+	&& EXTENSION_DIR=$PHP_EXTENSION_DIR \
+	./configure \
 		--build="$gnuArch" \
 		--with-config-file-path="$PHP_INI_DIR" \
 		--with-config-file-scan-dir="$PHP_INI_DIR/conf.d" \