--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/ext/attr-optimize.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,46 @@
+// Bug c++/83871 - wrong code due to attributes on distinct template
+// specializations
+// Test to verify that an explicit template specifialization does not
+// "inherit" attribute optimize from a primary template declared with
+// one.
+// { dg-do compile }
+// { dg-options "-O2 -Wall -fdump-tree-optimized" }
+
+enum Special { };
+
+void foptimize_none_primary_failed ();
+
+template <class T>
+void __attribute__ ((optimize ("no-printf-return-value")))
+foptimize_none ()
+{
+  // The call to snprintf and the test should be retained.
+  if (2 != __builtin_snprintf (0, 0, "%hhx", 0x12))
+    foptimize_none_primary_failed ();
+}
+
+void foptimize_none_special_failed ();
+
+template <>
+inline void
+foptimize_none<Special>()
+{
+  // The whole if statement should be eliminated.
+  if (3 != __builtin_snprintf (0, 0, "1%hhx", 0x12))
+    foptimize_none_special_failed ();
+}
+
+void test_primary ()
+{
+  foptimize_none<void>();
+  // { dg-final { scan-tree-dump-times "foptimize_none_primary_failed *\\(\\)" 1 "optimized" } }
+}
+
+void test_special ()
+{
+  // Should be eliminated.
+  foptimize_none<Special>();
+// { dg-final { scan-tree-dump-not "foptimize_none_special_failed *\\(\\)" "optimized" } }
+}
+
+// { dg-final { scan-tree-dump-times "__builtin_snprintf" 1 "optimized" } }