diff --git a/include/clang/Driver/Options.td b/include/clang/Driver/Options.td
index ebda0fb..d03ec94 100644
--- a/include/clang/Driver/Options.td
+++ b/include/clang/Driver/Options.td
@@ -822,7 +822,6 @@ def fdata_sections : Flag <["-"], "fdata-sections">, Group<f_Group>, Flags<[CC1O
   HelpText<"Place each data in its own section (ELF Only)">;
 def fdebug_types_section: Flag <["-"], "fdebug-types-section">, Group<f_Group>,
   Flags<[CC1Option]>, HelpText<"Place debug types in their own section (ELF Only)">;
-def f : Joined<["-"], "f">, Group<f_Group>;
 def g_Flag : Flag<["-"], "g">, Group<g_Group>,
   HelpText<"Generate source level debug information">, Flags<[CC1Option]>;
 def gline_tables_only : Flag<["-"], "gline-tables-only">, Group<g_Group>,
diff --git a/test/Driver/no-objc-default-synthesize-properties.m b/test/Driver/no-objc-default-synthesize-properties.m
index e380514..a034926 100644
--- a/test/Driver/no-objc-default-synthesize-properties.m
+++ b/test/Driver/no-objc-default-synthesize-properties.m
@@ -1,4 +1,4 @@
-// RUN: %clang  -fsyntax-only -fno-objc-default-synthesize-properties -fobjc-default-synthesize-properties %s 2>&1 | FileCheck %s
+// RUN: not %clang  -fsyntax-only -fno-objc-default-synthesize-properties -fobjc-default-synthesize-properties %s 2>&1 | FileCheck %s
 
 @interface I
 @property int P;
@@ -6,5 +6,5 @@
 
 @implementation I
 @end
-// CHECK: warning: argument unused during compilation: '-fno-objc-default-synthesize-properties'
-// CHECK: warning: argument unused during compilation: '-fobjc-default-synthesize-properties'
+// CHECK: error: unknown argument: '-fno-objc-default-synthesize-properties'
+// CHECK: error: unknown argument: '-fobjc-default-synthesize-properties'
diff --git a/test/Driver/unknown-arg.c b/test/Driver/unknown-arg.c
index 03ccc46..f834a0e 100644
--- a/test/Driver/unknown-arg.c
+++ b/test/Driver/unknown-arg.c
@@ -1,4 +1,4 @@
-// RUN: not %clang %s -cake-is-lie -%0 -%d -HHHH -munknown-to-clang-option -print-stats 2>&1 | \
+// RUN: not %clang %s -cake-is-lie -%0 -%d -HHHH -munknown-to-clang-option -print-stats -funknown-to-clang-option 2>&1 | \
 // RUN: FileCheck %s
 
 // CHECK: unknown argument: '-cake-is-lie'
@@ -7,9 +7,9 @@
 // CHECK: unknown argument: '-HHHH'
 // CHECK: unknown argument: '-munknown-to-clang-option'
 // CHECK: unknown argument: '-print-stats'
+// CHECK: unknown argument: '-funknown-to-clang-option'
 
 
-// RUN: %clang -S %s -o %t.s -funknown-to-clang-option -Wunknown-to-clang-option 2>&1 | FileCheck --check-prefix=IGNORED %s
+// RUN: %clang -S %s -o %t.s  -Wunknown-to-clang-option 2>&1 | FileCheck --check-prefix=IGNORED %s
 
-// IGNORED: warning: argument unused during compilation: '-funknown-to-clang-option'
 // IGNORED: warning: unknown warning option '-Wunknown-to-clang-option'