From 70d7d86505545e8a228897d6220c6f5b1cb3f76f Mon Sep 17 00:00:00 2001
From: =?utf8?q?J=C3=A9r=C3=B4me=20Loyet?= <fat@php.net>
Date: Wed, 1 Sep 2010 08:17:18 +0000
Subject: [PATCH] - Fixed bug #52725 (gcc builtin atomic functions were
 sometimes used when they were not available).

---
 sapi/fpm/config.m4        | 19 +++++++++++++++++++
 sapi/fpm/fpm/fpm_atomic.h |  2 +-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/sapi/fpm/config.m4 b/sapi/fpm/config.m4
index f32db6a368..0fd5669626 100644
--- a/sapi/fpm/config.m4
+++ b/sapi/fpm/config.m4
@@ -499,6 +499,24 @@ AC_DEFUN([AC_FPM_TRACE],
   fi
   
 ])
+
+AC_DEFUN([AC_FPM_BUILTIN_ATOMIC],
+[
+  AC_MSG_CHECKING([if gcc supports __sync_bool_compare_and_swap])
+  AC_TRY_LINK(,
+  [
+    int variable = 1;
+    return (__sync_bool_compare_and_swap(&variable, 1, 2)
+           && __sync_add_and_fetch(&variable, 1)) ? 1 : 0;
+  ],
+  [
+    AC_MSG_RESULT([yes])
+    AC_DEFINE(HAVE_BUILTIN_ATOMIC, 1, [Define to 1 if gcc supports __sync_bool_compare_and_swap() a.o.])
+  ],
+  [
+    AC_MSG_RESULT([no])
+  ])
+])
 dnl }}}
 
 AC_MSG_CHECKING(for FPM build)
@@ -518,6 +536,7 @@ if test "$PHP_FPM" != "no"; then
   AC_FPM_PRCTL
   AC_FPM_CLOCK
   AC_FPM_TRACE
+  AC_FPM_BUILTIN_ATOMIC
 
   PHP_ARG_WITH(fpm-user,,
   [  --with-fpm-user[=USER]  Set the user for php-fpm to run as. (default: nobody)], nobody, no)
diff --git a/sapi/fpm/fpm/fpm_atomic.h b/sapi/fpm/fpm/fpm_atomic.h
index e2e64d8a5d..5c93bfcb78 100644
--- a/sapi/fpm/fpm/fpm_atomic.h
+++ b/sapi/fpm/fpm/fpm_atomic.h
@@ -12,7 +12,7 @@
 #endif
 #include <sched.h>
 
-#if (__GNUC__) && (__GNUC__ >= 4 &&  __GNUC_MINOR__ >= 1)
+#ifdef HAVE_BUILTIN_ATOMIC
 
 /**
  * all the cases below (as provided by upstream) define:
-- 
2.40.0