Fix build on gcc < 5 (std::is_trivially_copyable missing)

[deliverable/binutils-gdb.git] / gdb / common / traits.h

diff --git a/gdb/common/traits.h b/gdb/common/traits.h
index 4f7161bdec424abcb973c47cb47f3df5c182e484..8c41b032f40e50c5877de8539d8449aa75f6638f 100644 (file)
--- a/gdb/common/traits.h
+++ b/gdb/common/traits.h
@@ -20,6 +20,19 @@
 
 #include <type_traits>
 
+/* GCC does not understand __has_feature.  */
+#if !defined(__has_feature)
+# define __has_feature(x) 0
+#endif
+
+/* HAVE_IS_TRIVIALLY_COPYABLE is defined as 1 iff
+   std::is_trivially_copyable is available.  GCC only implemented it
+   in GCC 5.  */
+#if (__has_feature(is_trivially_copyable) \
+     || (defined __GNUC__ && __GNUC__ >= 5))
+# define HAVE_IS_TRIVIALLY_COPYABLE 1
+#endif
+
 namespace gdb {
 
 /* Pre C++14-safe (CWG 1558) version of C++17's std::void_t.  See