Merge branch 'master' of https://github.com/jedisct1/libsodium

* 'master' of https://github.com/jedisct1/libsodium:
  Check if atomic operations are supported
  Remove a whitespace following trailing backslash in a Makefile

configure.ac

@@ -660,6 +660,17 @@ AS_IF([test "x$aligned_access_required" = "xyes"],
   [AC_MSG_RESULT(no)
    AC_DEFINE([CPU_UNALIGNED_ACCESS], [1], [unaligned memory access is supported])])
 
+AC_MSG_CHECKING(if atomic operations are supported)
+AC_LINK_IFELSE([AC_LANG_PROGRAM([[ ]], [[
+static volatile int _sodium_lock;
+__sync_lock_test_and_set(&_sodium_lock, 1);
+__sync_lock_release(&_sodium_lock);
+]]
+)],
+[AC_MSG_RESULT(yes)
+ AC_DEFINE([HAVE_ATOMIC_OPS], [1], [atomic operations are supported])],
+[AC_MSG_RESULT(no)])
+
 dnl Checks for functions and headers
 
 AS_IF([test "x$EMSCRIPTEN" = "x"],[

src/libsodium/sodium/core.c

@@ -123,7 +123,7 @@ sodium_crit_leave(void)
     return 0;
 }
 
-#elif defined(__GNUC__) && !defined(__EMSCRIPTEN__) && !defined(__native_client__)
+#elif defined(HAVE_ATOMIC_OPS) && !defined(__EMSCRIPTEN__) && !defined(__native_client__)
 
 static volatile int _sodium_lock;