diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 11ef7970378..1cfb70291f6 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -10677,6 +10677,7 @@ valid for all standard-compliant programs.
 It turns on @option{-ffast-math}, @option{-fallow-store-data-races}
 and the Fortran-specific @option{-fstack-arrays}, unless
 @option{-fmax-stack-var-size} is specified, and @option{-fno-protect-parens}.
+It turns off @option {-fsemantic-interposition}.
 
 @item -Og
 @opindex Og
diff --git a/gcc/opts.c b/gcc/opts.c
index 175b4635bb4..b16497e45b3 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -682,6 +682,7 @@ static const struct default_options default_options_table[] =
     /* -Ofast adds optimizations to -O3.  */
     { OPT_LEVELS_FAST, OPT_ffast_math, NULL, 1 },
     { OPT_LEVELS_FAST, OPT_fallow_store_data_races, NULL, 1 },
+    { OPT_LEVELS_FAST, OPT_fsemantic_interposition, NULL, 0 },
 
     { OPT_LEVELS_NONE, 0, NULL, 0 }
   };