Docker install PHP-7-fpm with Memcache extention ? fails with Cannot find config.m4

Here's how your Dockerfiles should look like:

PHP-FPM Dockerfile:

FROM php:7.0-fpm# ... RUN apt-get update && apt-get install -y \    libpq-dev \    libmemcached-dev \    curl# ... # Install Memcached for php 7RUN curl -L -o /tmp/memcached.tar.gz "https://github.com/php-memcached-dev/php-memcached/archive/php7.tar.gz" \    && mkdir -p /usr/src/php/ext/memcached \    && tar -C /usr/src/php/ext/memcached -zxvf /tmp/memcached.tar.gz --strip 1 \    && docker-php-ext-configure memcached \    && docker-php-ext-install memcached \    && rm /tmp/memcached.tar.gz# ... CMD ["php-fpm"]EXPOSE 9000

Memcached Dockerfile:

FROM memcached:latestCMD ["memcached"]EXPOSE 11211

This is taken from https://github.com/LaraDock/laradock

You need to run that command /usr/bin/phpize in the right folder.
See this Dockerfile as an example

RUN wget https://github.com/phpredis/phpredis/archive/2.2.5.zip; unzip 2.2.5.zipWORKDIR /tmp/php-redis/phpredis-2.2.5RUN /usr/bin/phpize; ./configure; make; make install

In your case, you did clone the repo php-memcached and make a cd in it, but that does not change the working directory for the next Dockerfile RUN directive.

Set that working directory before the RUN directive:

WORKDIR /php-memcachedRUN /usr/bin/phpize 

This work for me:

FROM php:7.1.1-fpmRUN apt-get updateRUN docker-php-ext-install mysqliRUN apt-get install -y \    libfreetype6-dev \    libjpeg62-turbo-dev \    libmcrypt-dev \    libpng12-dev \&& docker-php-ext-install -j$(nproc) iconv mcrypt \&& docker-php-ext-configure gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/ \&& docker-php-ext-install -j$(nproc) gdRUN apt-get install git -yRUN git --versionRUN apt-get install -y build-essential libmemcached-devRUN git clone https://github.com/php-memcached-dev/php-memcached.gitRUN cd php-memcached \&& git checkout php7 \&& phpize \&& ./configure --disable-memcached-sasl \&& make \&& make install