diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -3083,6 +3083,7 @@
 def miamcu : Flag<["-"], "miamcu">, Group<m_Group>, Flags<[NoXarchOption, CoreOption]>,
   HelpText<"Use Intel MCU ABI">;
 def mno_iamcu : Flag<["-"], "mno-iamcu">, Group<m_Group>, Flags<[NoXarchOption, CoreOption]>;
+def maccumulate_outgoing_args : Flag<["-"], "maccumulate-outgoing-args">, Group<clang_ignored_m_Group>;
 def malign_functions_EQ : Joined<["-"], "malign-functions=">, Group<clang_ignored_m_Group>;
 def malign_loops_EQ : Joined<["-"], "malign-loops=">, Group<clang_ignored_m_Group>;
 def malign_jumps_EQ : Joined<["-"], "malign-jumps=">, Group<clang_ignored_m_Group>;
diff --git a/clang/test/Driver/clang_f_opts.c b/clang/test/Driver/clang_f_opts.c
--- a/clang/test/Driver/clang_f_opts.c
+++ b/clang/test/Driver/clang_f_opts.c
@@ -304,6 +304,7 @@
 // RUN:     -fno-implement-inlines -fimplement-inlines                        \
 // RUN:     -fstack-check                                                     \
 // RUN:     -fforce-addr                                                      \
+// RUN:     -maccumulate-outgoing-args                                        \
 // RUN:     -malign-functions=100                                             \
 // RUN:     -malign-loops=100                                                 \
 // RUN:     -malign-jumps=100                                                 \