Squashed 'third_party/glog/' content from commit 9ef754a3023

git-subtree-dir: third_party/glog
git-subtree-split: 9ef754a3023e6fd10f20fe53dfca96dd898182e3

1 files changed, 25 insertions, 0 deletions

diff --git a/m4/stl_namespace.m4 b/m4/stl_namespace.m4
new file mode 100644
index 000000000000..989ad80696a3
--- /dev/null
+++ b/m4/stl_namespace.m4
@@ -0,0 +1,25 @@
+# We check what namespace stl code like vector expects to be executed in
+
+AC_DEFUN([AC_CXX_STL_NAMESPACE],
+  [AC_CACHE_CHECK(
+      what namespace STL code is in,
+      ac_cv_cxx_stl_namespace,
+      [AC_REQUIRE([AC_CXX_NAMESPACES])
+      AC_LANG_SAVE
+      AC_LANG_CPLUSPLUS
+      AC_TRY_COMPILE([#include <vector>],
+                     [vector<int> t; return 0;],
+                     ac_cv_cxx_stl_namespace=none)
+      AC_TRY_COMPILE([#include <vector>],
+                     [std::vector<int> t; return 0;],
+                     ac_cv_cxx_stl_namespace=std)
+      AC_LANG_RESTORE])
+   if test "$ac_cv_cxx_stl_namespace" = none; then
+      AC_DEFINE(STL_NAMESPACE,,
+                [the namespace where STL code like vector<> is defined])
+   fi
+   if test "$ac_cv_cxx_stl_namespace" = std; then
+      AC_DEFINE(STL_NAMESPACE,std,
+                [the namespace where STL code like vector<> is defined])
+   fi
+])