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
@@ -3258,6 +3258,7 @@
 defm ipa_cp : BooleanFFlag<"ipa-cp">,
     Group<clang_ignored_gcc_optimization_f_Group>;
 defm ivopts : BooleanFFlag<"ivopts">, Group<clang_ignored_gcc_optimization_f_Group>;
+def : Flag<["-"], "fno-semantic-interposition">, Group<clang_ignored_f_Group>;
 defm non_call_exceptions : BooleanFFlag<"non-call-exceptions">, Group<clang_ignored_f_Group>;
 defm peel_loops : BooleanFFlag<"peel-loops">, Group<clang_ignored_gcc_optimization_f_Group>;
 defm permissive : BooleanFFlag<"permissive">, Group<clang_ignored_f_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
@@ -251,6 +251,7 @@
 // RUN:     -fexec-charset=UTF-8                                             \
 // RUN:     -fivopts -fno-ivopts                                              \
 // RUN:     -fnon-call-exceptions -fno-non-call-exceptions                    \
+// RUN:     -fno-semantic-interposition                                       \
 // RUN:     -fpermissive -fno-permissive                                      \
 // RUN:     -fdefer-pop -fno-defer-pop                                        \
 // RUN:     -fprefetch-loop-arrays -fno-prefetch-loop-arrays                  \