diff --git a/debian/patches/CXXFLAGS.dpatch b/debian/patches/CXXFLAGS.dpatch
--- /dev/null
@@ -0,0 +1,45 @@
+#! /bin/sh /usr/share/dpatch/dpatch-run
+## CXXFLAGS.dpatch by Sebastian Harl <tokkee@debian.org>
+##
+## DP: Remove -O3 from CXXFLAGS.
+
+@DPATCH@
+
+diff a/configure b/configure
+--- a/configure
++++ b/configure
+@@ -19378,8 +19378,6 @@ fi
+ # Check whether --enable-debug was given.
+ if test "${enable_debug+set}" = set; then
+ enableval=$enable_debug; if test "$enable_debug" = "yes" ; then
+- temp_CXXFLAGS=`echo $CXXFLAGS | sed "s/-O./ /; s/-g//"`
+- CXXFLAGS="-g $temp_CXXFLAGS"
+ cat >>confdefs.h <<\_ACEOF
+ #define DEBUG 1
+ _ACEOF
+@@ -19387,8 +19385,6 @@ _ACEOF
+ fi
+ else
+ enable_debug="no"
+- temp_CXXFLAGS=`echo $CXXFLAGS | sed "s/-O./ /; s/-g//"`
+- CXXFLAGS="-O3 $temp_CXXFLAGS"
+
+ cat >>confdefs.h <<\_ACEOF
+ #define NDEBUG 1
+diff a/configure.ac b/configure.ac
+--- a/configure.ac
++++ b/configure.ac
+@@ -37,13 +37,9 @@ AC_ARG_ENABLE(debug,
+ AC_HELP_STRING([--enable-debug],
+ [Enable debug symbols and asserts]),
+ [if test "$enable_debug" = "yes" ; then
+- temp_CXXFLAGS=`echo $CXXFLAGS | sed "s/-O./ /; s/-g//"`
+- CXXFLAGS="-g $temp_CXXFLAGS"
+ AC_DEFINE([DEBUG])
+ fi],
+ [enable_debug="no"
+- temp_CXXFLAGS=`echo $CXXFLAGS | sed "s/-O./ /; s/-g//"`
+- CXXFLAGS="-O3 $temp_CXXFLAGS"
+ AC_DEFINE(NDEBUG, 1, [Disable assertion checks])
+
+