# PCRE symbol visibility bug - Thread: https://externals.io/message/42209 - Original archive: https://news-web.php.net/php.internals/42209 - Started by shire on 2008-12-09T22:09:11+00:00 - Messages: 2 - Reply by email to internals@lists.php.net - More for agents: search with https://externals.io/search.md?q={query} · JSON API at https://externals.io/api · documentation at https://externals.io/llms.txt --- ## #42209 — shire — 2008-12-09T22:09:11+00:00 URL: https://externals.io/message/42209#42209 When using GCC 4.x with php-5.3, and an extension (such as APC) that references PCRE functions (pcre_exec) that are bundled with PHP in the pcre extension. The symbols defined in the PHP binaries don't include a visibility "default" attribute, and are currently set to "hidden" in CFLAGS. This makes the symbols unavailable to any .so extension, which triggers a fault. It seems like adding the visibility attribute to the bundled PHP code should fix this, but I wanted to post here as perhaps someone has a better suggestion. It would probably be better if this didn't modify the pcrelib/* files. I've included a patch as a possible fix, I can go ahead and commit this if this is what we want, but I'm hoping someone has some other suggestions. before: shire@shirebook:/usr/local/apache/libexec$ nm `which php` | grep pcre_exec 000266b4 t _php_pcre_exec after: shire@shirebook:/usr/local/apache/libexec$ nm `which php` | grep pcre_exec 000266b4 T _php_pcre_exec cvs diff: Diffing . cvs diff: Diffing doc Index: pcre_internal.h =================================================================== RCS file: /repository/php-src/ext/pcre/pcrelib/pcre_internal.h,v retrieving revision 1.1.2.1.2.5.2.5 diff -u -r1.1.2.1.2.5.2.5 pcre_internal.h --- pcre_internal.h 9 Sep 2008 07:55:08 -0000 1.1.2.1.2.5.2.5 +++ pcre_internal.h 9 Dec 2008 22:05:57 -0000 @@ -119,9 +119,17 @@ # endif # else # ifdef __cplusplus -# define PCRE_EXP_DECL extern "C" +# if defined(__GNUC__) && __GNUC__ >= 4 +# define PCRE_EXP_DECL __attribute__ ((visibility("default"))) extern "C" +# else +# define PCRE_EXP_DECL extern "C" +# endif # else -# define PCRE_EXP_DECL extern +# if defined(__GNUC__) && __GNUC__ >= 4 +# define PCRE_EXP_DECL __attribute__ ((visibility("default"))) extern +# else +# define PCRE_EXP_DECL extern +# endif # endif # ifndef PCRE_EXP_DEFN # define PCRE_EXP_DEFN PCRE_EXP_DECL -shire --- ## #42211 — Nuno Lopes — 2008-12-10T10:16:52+00:00 URL: https://externals.io/message/42209#42211 · In reply to: #42209 I've commited a fix. I didn't patch the pcre_internal.h file directly, otherwise the patch would be reverted on the next upgrade of the pcre lib. Thanks, Nuno ----- Original Message ----- From: "shire" To: "PHP Internals List" Sent: Tuesday, December 09, 2008 10:09 PM Subject: [PHP-DEV] PCRE symbol visibility bug > > When using GCC 4.x with php-5.3, and an extension (such as APC) that > references PCRE functions (pcre_exec) that are bundled with PHP in the > pcre extension. The symbols defined in the PHP binaries don't include a > visibility "default" attribute, and are currently set to "hidden" in > CFLAGS. This makes the symbols unavailable to any .so extension, which > triggers a fault. > > It seems like adding the visibility attribute to the bundled PHP code > should fix this, but I wanted to post here as perhaps someone has a > better suggestion. It would probably be better if this didn't modify the > pcrelib/* files. I've included a patch as a possible fix, I can go ahead > and commit this if this is what we want, but I'm hoping someone has some > other suggestions. > > > before: > shire@shirebook:/usr/local/apache/libexec$ nm `which php` | grep > pcre_exec > 000266b4 t _php_pcre_exec > > after: > shire@shirebook:/usr/local/apache/libexec$ nm `which php` | grep > pcre_exec > 000266b4 T _php_pcre_exec > > > cvs diff: Diffing . > cvs diff: Diffing doc > Index: pcre_internal.h > =================================================================== > RCS file: /repository/php-src/ext/pcre/pcrelib/pcre_internal.h,v > retrieving revision 1.1.2.1.2.5.2.5 > diff -u -r1.1.2.1.2.5.2.5 pcre_internal.h > --- pcre_internal.h 9 Sep 2008 07:55:08 -0000 1.1.2.1.2.5.2.5 > +++ pcre_internal.h 9 Dec 2008 22:05:57 -0000 > @@ -119,9 +119,17 @@ > # endif > # else > # ifdef __cplusplus > -# define PCRE_EXP_DECL extern "C" > +# if defined(__GNUC__) && __GNUC__ >= 4 > +# define PCRE_EXP_DECL __attribute__ > ((visibility("default"))) extern "C" > +# else > +# define PCRE_EXP_DECL extern "C" > +# endif > # else > -# define PCRE_EXP_DECL extern > +# if defined(__GNUC__) && __GNUC__ >= 4 > +# define PCRE_EXP_DECL __attribute__ > ((visibility("default"))) extern > +# else > +# define PCRE_EXP_DECL extern > +# endif > # endif > # ifndef PCRE_EXP_DEFN > # define PCRE_EXP_DEFN PCRE_EXP_DECL > > > -shire