Description:
------------
Using either gcc version 4.9.2 (Debian 4.9.2-10) or gcc version 6.1.0 (GCC).

Build fails with the following error:
main/internal_functions.c:107:2: error: ‘phpext_igbinary_ptr’ undeclared here (not in a function)

All the sources are stored under /usr/local/src

Test script:
---------------
Here is my build script (I tried slimming it down, but then the build worked):
cd /usr/local/src/php-7.1.6
rm -R ext/igbinary 2>/dev/null ; mkdir ext/igbinary ; cp -R ../igbinary-2.0.1/* ext/igbinary/
rm -R ext/redis 2>/dev/null ; mkdir ext/redis ; cp -R ../redis-3.1.2/* ext/redis/
cd /usr/local/src/php-7.1.6
rm configure ; ./buildconf --force ; make clean
./configure --prefix=/usr/local/php71 --disable-all --enable-igbinary --enable-redis --disable-redis-session --enable-redis-igbinary
make


Expected result:
----------------
Build complete.
Don't forget to run 'make test'.

Actual result:
--------------
/usr/local/src/php-7.1.6/Zend/zend_execute.c: In function ‘zend_check_arg_type’:
/usr/local/src/php-7.1.6/Zend/zend_execute.c:958:3: warning: ‘ce’ may be used uninitialized in this function [-Wmaybe-uninitialized]
   zend_verify_arg_error(zf, cur_arg_info, arg_num, ce, arg);
   ^
/usr/local/src/php-7.1.6/Zend/zend_execute.c:947:20: note: ‘ce’ was declared here
  zend_class_entry *ce;
                    ^
/bin/bash /usr/local/src/php-7.1.6/libtool --silent --preserve-dup-deps --mode=compile cc -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -Imain/ -I/usr/local/src/php-7.1.6/main/ -DPHP_ATOM_INC -I/usr/local/src/php-7.1.6/include -I/usr/local/src/php-7.1.6/main -I/usr/local/src/php-7.1.6 -I/usr/local/src/php-7.1.6/ext/date/lib -I/usr/local/src/php-7.1.6/ext -I/usr/local/php71/include/php/ext/date/lib -I/usr/local/src/php-7.1.6/TSRM -I/usr/local/src/php-7.1.6/Zend  -Wall  -g -O2 -fvisibility=hidden -DZEND_SIGNALS   -c main/internal_functions_cli.c -o main/internal_functions_cli.lo
main/internal_functions_cli.c:42:2: error: ‘phpext_igbinary_ptr’ undeclared here (not in a function)
  phpext_igbinary_ptr,
  ^
Makefile:781: recipe for target 'main/internal_functions_cli.lo' failed
make: *** [main/internal_functions_cli.lo] Error 1