PCRE symbol visibility bug
| From: | shire | Date: | Tue, 09 Dec 2008 22:09:11 +0000 |
| Subject: | PCRE symbol visibility bug | ||
| Groups: | php.internals | ||
| Request: | Send a blank email to internals+get-42209@lists.php.net to get a copy of this message | ||
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