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Date: Mon, 18 Sep 2017 13:28:35 +0200
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Subject: PCRE JIT broken in PHP 7.2
From: giovanni@giacobbi.net (Giovanni Giacobbi)

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Greetings,

just an heads up, I started testing my project with PHP 7.2.0RC2 but it was
causing a segmentation fault.

I tracked down the problem to preg_match(), in particular when JIT is
enabled and ONLY when running through Apache2 with event MPM. This problem
does not occur with command line invocation.

Here are the versions I tested, same environment:
7.1.9  works with PCRE JIT enabled
7.2.0alpha1   broken
7.2.0rc2  broken

Build command line:
./configure \
  --with-apxs2=/usr/local/apache2/bin/apxs \
  --with-fpm-user=httpd \
  --with-fpm-group=httpd \
  --disable-cgi \
  --enable-intl \
  --with-layout=GNU \
  --enable-maintainer-zts \
  --with-gettext=static \
  --with-iconv \
  --with-mysqli=mysqlnd \
  --enable-exif \
  --with-openssl \
  --with-curl

The effect i observed is the following:

var_dump(preg_match('/^a/', "a"));    => int(0)
var_dump(preg_match('/a/', "a"));     => segmentation fault

If you need any further information let me know.

Kind regards

-- 
Giovanni Giacobbi

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