Source release 15.2.0

third_party/protobuf/configure.ac

@@ -17,7 +17,7 @@ AC_PREREQ(2.59)
 # In the SVN trunk, the version should always be the next anticipated release
 # version with the "-pre" suffix.  (We used to use "-SNAPSHOT" but this pushed
 # the size of one file name in the dist tarfile over the 99-char limit.)
-AC_INIT([Protocol Buffers],[3.6.1],[protobuf@googlegroups.com],[protobuf])
+AC_INIT([Protocol Buffers],[3.8.0],[protobuf@googlegroups.com],[protobuf])
 
 AM_MAINTAINER_MODE([enable])
 
@@ -165,6 +165,26 @@ AS_IF([test "$with_zlib" != no], [
 ])
 AM_CONDITIONAL([HAVE_ZLIB], [test $HAVE_ZLIB = 1])
 
+# Add -std=c++11 if necesssary. It is important for us to do this before the
+# libatomic check below, since that also depends on C++11.
+AX_CXX_COMPILE_STDCXX([11], [noext], [mandatory])
+
+dnl On some platforms, std::atomic needs a helper library
+AC_MSG_CHECKING(whether -latomic is needed)
+AC_LINK_IFELSE([AC_LANG_SOURCE([[
+  #include <atomic>
+  #include <cstdint>
+  std::atomic<std::int64_t> v;
+  int main() {
+    return v;
+  }
+]])], STD_ATOMIC_NEED_LIBATOMIC=no, STD_ATOMIC_NEED_LIBATOMIC=yes)
+AC_MSG_RESULT($STD_ATOMIC_NEED_LIBATOMIC)
+if test "x$STD_ATOMIC_NEED_LIBATOMIC" = xyes; then
+  LIBATOMIC_LIBS="-latomic"
+fi
+AC_SUBST([LIBATOMIC_LIBS])
+
 AS_IF([test "$with_protoc" != "no"], [
   PROTOC=$with_protoc
   AS_IF([test "$with_protoc" = "yes"], [
@@ -189,15 +209,6 @@ AM_CONDITIONAL([HAVE_PTHREAD], [test "x$ax_pthread_ok" = "xyes"])
 # We still keep this for improving pbconfig.h for unsupported platforms.
 AC_CXX_STL_HASH
 
-case "$target_os" in
-  mingw* | cygwin* | win* | aix*)
-    ;;
-  *)
-    # Need to link against rt on Solaris
-    AC_SEARCH_LIBS([sched_yield], [rt], [], [AC_MSG_FAILURE([sched_yield was not found on your system])])
-    ;;
-esac
-
 # Enable ObjC support for conformance directory on OS X.
 OBJC_CONFORMANCE_TEST=0
 case "$target_os" in
@@ -207,8 +218,6 @@ case "$target_os" in
 esac
 AM_CONDITIONAL([OBJC_CONFORMANCE_TEST], [test $OBJC_CONFORMANCE_TEST = 1])
 
-AX_CXX_COMPILE_STDCXX([11], [noext], [mandatory])
-
 # HACK:  Make gmock's configure script pick up our copy of CFLAGS and CXXFLAGS,
 #   since the flags added by ACX_CHECK_SUNCC must be used when compiling gmock
 #   too.