diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index d4377c9a0b..412fb58710 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -198,9 +198,11 @@ def Unused : DiagGroup<"unused",
                         DiagCategory<"Unused Entity Issue">;
 
 // Format settings.
-def Format : DiagGroup<"format", [FormatExtraArgs, FormatZeroLength, NonNull]>,
+def FormatSecurity : DiagGroup<"format-security">;
+def Format : DiagGroup<"format",
+                       [FormatExtraArgs, FormatZeroLength, NonNull,
+                        FormatSecurity]>,
              DiagCategory<"Format String Issue">;
-def FormatSecurity : DiagGroup<"format-security", [Format]>;
 def FormatNonLiteral : DiagGroup<"format-nonliteral", [FormatSecurity]>;
 def FormatY2K : DiagGroup<"format-y2k", [Format]>;
 def Format2 : DiagGroup<"format=2",
diff --git a/test/Sema/format-strings.c b/test/Sema/format-strings.c
index be506d7c6b..fe4f4567cb 100644
--- a/test/Sema/format-strings.c
+++ b/test/Sema/format-strings.c
@@ -340,3 +340,13 @@ void posix_extensions() {
   printf("%'f\n", (float) 1.0); // no-warning
   printf("%'p\n", (void*) 0); // expected-warning{{results in undefined behavior with 'p' conversion specifier}}
 }
+
+// PR8486
+//
+// Test what happens when -Wformat is on, but -Wformat-security is off.
+#pragma GCC diagnostic warning "-Wformat"
+#pragma GCC diagnostic ignored "-Wformat-security"
+
+void pr8486() {
+  printf("%s", 1); // expected-warning{{conversion specifies type 'char *' but the argument has type 'int'}}
+}