编译php7.1.4出现 undefined reference to isfinite

我在 CentOS5.5 上编译 php7.1.4 出现错误：

ext/standard/.libs/var.o: In function `php_var_export_ex':
/PHP/32/source/php7.1.4_zts/ext/standard/var.c:473: undefined reference to `isfinite'
main/.libs/php_variables.o: In function `zend_dval_to_lval':
/PHP/32/source/php7.1.4_zts/Zend/zend_operators.h:117: undefined reference to `isfinite'
Zend/.libs/zend_operators.o: In function `zendi_smart_strcmp':
/PHP/32/source/php7.1.4_zts/Zend/zend_operators.c:2789: undefined reference to `isfinite'
Zend/.libs/zend_operators.o: In function `zend_dval_to_lval':
/PHP/32/source/php7.1.4_zts/Zend/zend_operators.h:117: undefined reference to `isfinite'
/PHP/32/source/php7.1.4_zts/Zend/zend_operators.h:117: undefined reference to `isfinite'
Zend/.libs/zend_operators.o:/PHP/32/source/php7.1.4_zts/Zend/zend_operators.h:117: more undefined references to `isfinite' follow
collect2: ld returned 1 exit status
make: *** [sapi/cli/php] Error 1

系统信息 :

[root@localhost]# cat /etc/issue
CentOS release 5.5 (Final)
Kernel \r on an \m

[root@localhost]# gcc --version
gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-55)
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[root@localhost]# ldd --version
ldd (GNU libc) 2.5
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Written by Roland McGrath and Ulrich Drepper.

[root@localhost]# autoconf --version
autoconf (GNU Autoconf) 2.59
Written by David J. MacKenzie and Akim Demaille.
Copyright (C) 2003 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[root@localhost]# m4 --version
GNU M4 1.4.5
Written by Rene' Seindal.
Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

网上找了一圈发现 GCC 4.1.2 版本还不能支持

isfinite

, GCC4.3.3 才开始支持

isfinite

.

但是我又不想升级 GCC，那是否还有其他方法呢？

经过测试， php7.1.2 之前的版本都可以编译通过，php7.1.3之后的版本一编译就报上面的错误

我的配置参数为 :

./configure --prefix=/target/php --with-config-file-path=/target/php/etc --enable-maintainer-zts --with-iconv --with-zlib --enable-xml --enable-bcmath --enable-shmop --enable-sysvsem --enable-inline-optimization --enable-mbregex --enable-mbstring --enable-ftp --enable-gd-native-ttf --enable-pcntl --enable-sockets --with-xmlrpc --enable-zip --enable-soap --without-pear --with-gettext --enable-session

为什么 php7.1.2 可以编译通过，而 php7.1.3 之后的版本就不行了呢？

我对比了 php7.1.2 和 php7.1.3 的 config.log ：

>>> php7.1.2 config.log
configure:95485: checking for isfinite
configure:95485: gcc -m32 -o conftest -I/usr/include -g -O2 -fvisibility=hidden -pthread  -D_REENTRANT  conftest.c  >&5
/tmp/ccsJhzxB.o: In function `main':
/usr/local/src/php-7.1.2/conftest.c:514: undefined reference t
4000
o `isfinite'
.....
ac_cv_func_isfinite=no

>>> php7.1.3 config.log
configure:95505: checking whether isfinite is declared
configure:95505: gcc -m32 -c -I/usr/include -g -O2 -fvisibility=hidden -pthread  -D_REENTRANT conftest.c >&5
configure:95505: $? = 0
.....
#define HAVE_DECL_ISFINITE 1
.....
ac_cv_have_decl_isfinite=yes

通过观察可以发现 php7.1.2 的

configure

脚本可以正确检测 gcc 是否支持

isfinite

而 php7.1.3 之后的脚本总是检测出 gcc 能够支持

isfinite

OK，那就修改

configure

使其认为 gcc 不支持

isfinite

是否就行了呢？

在 php7.1.3 版本你需要修改

configure

文件使其没有定义

HAVE_DECL_ISFINITE

等几个宏才可以

推荐修改 php7.1.4 版本的

configure

文件，因为 php7.1.4 打过一个补丁

https://github.com/php/php-src/commit/2e8308260513015dbf80ff0239eca79dbca4f36e

修改 php7.1.4 的

configure

文件的 95508、95519 和 95530 行

将

ac_have_decl=1

修改为

ac_have_decl=0

95505  ac_fn_c_check_decl "$LINENO" "isfinite" "ac_cv_have_decl_isfinite" "#include <math.h>
95506  "
95507  if test "x$ac_cv_have_decl_isfinite" = xyes; then :
95508    ac_have_decl=1    #修改为 ac_have_decl=0
95509  else
95510    ac_have_decl=0
95511  fi
95512
95513  cat >>confdefs.h <<_ACEOF
95514  #define HAVE_DECL_ISFINITE $ac_have_decl
95515  _ACEOF
95516  ac_fn_c_check_decl "$LINENO" "isnan" "ac_cv_have_decl_isnan" "#include <math.h>
95517  "
95518  if test "x$ac_cv_have_decl_isnan" = xyes; then :
95519    ac_have_decl=1    #修改为 ac_have_decl=0
95520  else
95521    ac_have_decl=0
95522  fi
95523
95524  cat >>confdefs.h <<_ACEOF
95525  #define HAVE_DECL_ISNAN $ac_have_decl
95526  _ACEOF
95527  ac_fn_c_check_decl "$LINENO" "isinf" "ac_cv_have_decl_isinf" "#include <math.h>
95528  "
95529  if test "x$ac_cv_have_decl_isinf" = xyes; then :
95530    ac_have_decl=1    #修改为 ac_have_decl=0
95531  else
95532    ac_have_decl=0
95533  fi

修改之后可以看到 config.log 中

| #define HAVE_DECL_ISFINITE 0
| #define HAVE_DECL_ISNAN 0
| #define HAVE_DECL_ISINF 0

然后 make 一下，php7.1.4 果然可以正常编译了。当然这只是临时办法，还是期待 php 后续版本能修复这个问题.