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" shire@php.net
To: "PHP Internals List" internals@lists.php.net
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