1. 下载安装编译工具
yum groupinstall 'Development Tools'
2.安装依赖包
yum install libxml2 libxml2-devel openssl openssl-devel bzip2 bzip2-devel libcurl libcurl-devel libjpeg libjpeg-devel libpng libpng-devel freetype freetype-devel gmp gmp-devel libmcrypt libmcrypt-devel readline readline-devel libxslt libxslt-devel zlib zlib-devel glibc glibc-devel glib2 glib2-devel ncurses curl gdbm-devel db4-devel libXpm-devel libX11-devel gd-devel gmp-devel expat-devel xmlrpc-c xmlrpc-c-devel libicu-devel libmcrypt-devel libmemcached-devel
3.下载并解压php7.4
wget http://php.net/distributions/php-7.4.0.tar.gz
tar -zxvf php-7.4.0.tar.gz
cd php-7.4.0
4.编译安装（./configure --help 查看编译参数）
编译前，新增用户组，用户，用于编译使用
groupadd www
useradd -g www www
开始编译（根据自己需要增减）
./configure \
--prefix=/usr/local/php \
--with-config-file-path=/etc \
--with-fpm-user=www \
--with-fpm-group=www \
--with-curl \
--with-freetype-dir \
--enable-gd \
--with-gettext \
--with-iconv-dir \
--with-kerberos \
--with-libdir=lib64 \
--with-libxml-dir \
--with-mysqli \
--with-openssl \
--with-pcre-regex \
--with-pdo-mysql \
--with-pdo-sqlite \
--with-pear \
--with-png-dir \
--with-jpeg-dir \
--with-xmlrpc \
--with-xsl \
--with-zlib \
--with-bz2 \
--with-mhash \
--enable-fpm \
--enable-bcmath \
--enable-libxml \
--enable-inline-optimization \
--enable-mbregex \
--enable-mbstring \
--enable-opcache \
--enable-pcntl \
--enable-shmop \
--enable-soap \
--enable-sockets \
--enable-sysvsem \
--enable-sysvshm \
--enable-xml \
--enable-zip \
--enable-fpm
这里需要注意的是在php7.4 编译参数 --with-gd 要改成了 --enable-gd
当报错checking for libzip... configure: error: system libzip must be upgraded to version >= 0.11
#先删除旧版本
yum remove -y libzip #下载编译安装
wget https://nih.at/libzip/libzip-1.2.0.tar.gz
tar -zxvf libzip-1.2..tar.gz
cd libzip-1.2.
./configure
make && make install
error： Package requirements (sqlite3 > 3.7.4) were not met
yum install libsqlite3x-devel -y
error: Package requirements (oniguruma) were not met
yum install oniguruma-devel -y
当yum install 提示 "没可用软件包"
yum install -y epel-release
off_t undefined 报错
configure: error: off_t undefined; check your library configuration
off_t 类型是在 头文件 unistd.h中定义的，
在32位系统 编程成 long int ，64位系统则编译成 long long int ，
在进行编译的时候 是默认查找64位的动态链接库，
但是默认情况下 centos 的动态链接库配置文件/etc/ld.so.conf里并没有加入搜索路径，
这个时候需要将 /usr/local/lib64 /usr/lib64 这些针对64位的库文件路径加进去。
#添加搜索路径到配置文件
echo '/usr/local/lib64
/usr/local/lib
/usr/lib
/usr/lib64'>>/etc/ld.so.conf #然后 更新配置
ldconfig -v
/usr/local/include/zip.h:59:21: fatal error: zipconf.h: No such file or directory
cp /usr/local/lib/libzip/include/zipconf.h /usr/local/include/zipconf.h
编译没问题了，执行make && make install 安装完毕
5.配置环境
执行完安装命令后php7.4就已经安装在到了/usr/local/php目录下了
/usr/local/php/bin/php -v
查看版本
添加环境变量
vim /etc/profile
添加到最后
PATH=$PATH:/usr/local/php/bin
export PATH
更新环境变量
source /etc/profile
查看版本
php -v
6.配置php-fpm
cp php.ini-production /etc/php.ini
cp /usr/local/php/etc/php-fpm.conf.default /usr/local/php/etc/php-fpm.conf
cp /usr/local/php/etc/php-fpm.d/www.conf.default /usr/local/php/etc/php-fpm.d/www.conf
cp sapi/fpm/init.d.php-fpm /etc/init.d/php-fpm
chmod +x /etc/init.d/php-fpm
启动php-fpm
/etc/init.d/php-fpm start
或者
service php-fpm start