[Boost-commit] svn:boost r74822 - trunk/boost/asio/detail

Subject: [Boost-commit] svn:boost r74822 - trunk/boost/asio/detail
From: chris_at_[hidden]
Date: 2011-10-08 17:31:26

Author: chris_kohlhoff
Date: 2011-10-08 17:31:26 EDT (Sat, 08 Oct 2011)
New Revision: 74822
URL: http://svn.boost.org/trac/boost/changeset/74822

Log:
Fix crash due to gcc_x86_fenced_block that shows up when using the Intel C++ compiler. Refs #5763
Text files modified: 
   trunk/boost/asio/detail/gcc_x86_fenced_block.hpp |    23 ++++++++++++++++++-----                 
   1 files changed, 18 insertions(+), 5 deletions(-)

Modified: trunk/boost/asio/detail/gcc_x86_fenced_block.hpp
==============================================================================
--- trunk/boost/asio/detail/gcc_x86_fenced_block.hpp	(original)
+++ trunk/boost/asio/detail/gcc_x86_fenced_block.hpp	2011-10-08 17:31:26 EDT (Sat, 08 Oct 2011)
@@ -32,22 +32,35 @@
   // Constructor.
   gcc_x86_fenced_block()
   {
-    barrier();
+    barrier1();
   }
 
   // Destructor.
   ~gcc_x86_fenced_block()
   {
-    barrier();
+    barrier2();
   }
 
 private:
-  static int barrier()
+  static int barrier1()
   {
-    int r = 0;
-    __asm__ __volatile__ ("xchgl %%eax, %0" : "=m" (r) : : "memory", "cc");
+    int r = 0, m = 1;
+    __asm__ __volatile__ (
+        "xchgl %0, %1" :
+        "=r"(r), "=m"(m) :
+        "0"(1), "m"(m) :
+        "memory", "cc");
     return r;
   }
+
+  static void barrier2()
+  {
+#if defined(__SSE2__)
+    __asm__ __volatile__ ("mfence" ::: "memory");
+#else // defined(__SSE2__)
+    barrier1();
+#endif // defined(__SSE2__)
+  }
 };
 
 } // namespace detail