diff -durN gcc-4.4.5.orig/gcc/doc/invoke.texi gcc-4.4.5/gcc/doc/invoke.texi

 --- gcc-4.4.5.orig/gcc/doc/invoke.texi	2010-10-09 22:59:03.000000000 +0200

 +++ gcc-4.4.5/gcc/doc/invoke.texi	2010-10-09 22:59:33.000000000 +0200

 @@ -5432,6 +5432,11 @@

  Please note the warning under @option{-fgcse} about

  invoking @option{-O2} on programs that use computed gotos.

 +NOTE: In Gentoo, @option{-D_FORTIFY_SOURCE=2} is set by default, and is

 +activated when @option{-O} is set to 2 or higher.  This enables additional

 +compile-time and run-time checks for several libc functions.  To disable,

 +specify either @option{-U_FORTIFY_SOURCE} or @option{-D_FORTIFY_SOURCE=0}.

 +

  @item -O3

  @opindex O3

  Optimize yet more.  @option{-O3} turns on all optimizations specified

 diff -durN gcc-4.4.5.orig/gcc/gcc.c gcc-4.4.5/gcc/gcc.c

 --- gcc-4.4.5.orig/gcc/gcc.c	2010-01-09 01:05:06.000000000 +0100

 +++ gcc-4.4.5/gcc/gcc.c	2010-10-09 22:59:33.000000000 +0200

 @@ -807,6 +807,7 @@

   %{H} %C %{D*&U*&A*} %{i*} %Z %i\

   %{fmudflap:-D_MUDFLAP -include mf-runtime.h}\

   %{fmudflapth:-D_MUDFLAP -D_MUDFLAPTH -include mf-runtime.h}\

 + %{!D_FORTIFY_SOURCE:%{!D_FORTIFY_SOURCE=*:%{!U_FORTIFY_SOURCE:-D_FORTIFY_SOURCE=2}}}\

   %{E|M|MM:%W{o*}}";

  /* This contains cpp options which are common with cc1_options and are passed