diff --git a/macros.qt5 b/macros.qt5
index ee9b259..9fb7807 100644
--- a/macros.qt5
+++ b/macros.qt5
@@ -18,14 +18,16 @@
 %_qt5_sysconfdir %{_qt5_settingsdir}
 %_qt5_translationdir %{_datadir}/qt5/translations
 
-%_qt5_ldflags %{?__global_ldflags} @@QT5_RPM_LD_FLAGS@@
+%_qt5_cflags %{nil}@@QT5_CFLAGS@@
+%_qt5_cxxflags %{nil}@@QT5_CXXFLAGS@@
+%_qt5_ldflags %{nil}%{?__global_ldflags} @@QT5_RPM_LD_FLAGS@@
 %_qt5_optflags %{optflags} @@QT5_RPM_OPT_FLAGS@@
 
 %_qt5_qmake_flags \\\
-  QMAKE_CFLAGS_DEBUG="${CFLAGS:-%{_qt5_optflags}}" \\\
-  QMAKE_CFLAGS_RELEASE="${CFLAGS:-%{_qt5_optflags}}" \\\
-  QMAKE_CXXFLAGS_DEBUG="${CXXFLAGS:-%{_qt5_optflags}}" \\\
-  QMAKE_CXXFLAGS_RELEASE="${CXXFLAGS:-%{_qt5_optflags}}" \\\
+  QMAKE_CFLAGS_DEBUG="${CFLAGS:-%{_qt5_optflags} %{?_qt5_cflags}}" \\\
+  QMAKE_CFLAGS_RELEASE="${CFLAGS:-%{_qt5_optflags} %{?_qt5_cflags}}" \\\
+  QMAKE_CXXFLAGS_DEBUG="${CXXFLAGS:-%{_qt5_optflags} %{?_qt5_cxxflags}}" \\\
+  QMAKE_CXXFLAGS_RELEASE="${CXXFLAGS:-%{_qt5_optflags} %{?_qt5_cxxflags}}" \\\
   QMAKE_LFLAGS_DEBUG="${LDFLAGS:-%{_qt5_ldflags}}" \\\
   QMAKE_LFLAGS_RELEASE="${LDFLAGS:-%{_qt5_ldflags}}" \\\
   QMAKE_STRIP=
diff --git a/qt5-qtbase.spec b/qt5-qtbase.spec
index 689ae25..291d80a 100644
--- a/qt5-qtbase.spec
+++ b/qt5-qtbase.spec
@@ -30,6 +30,14 @@
 
 %if 0%{?fedora} > 23
 %global journald -journald
+# gcc6: FTBFS
+%global qt5_deprecated_flag -Wno-deprecated-declaration
+# gcc6: Qt assumes this in places
+%global qt5_null_flag -fno-delete-null-pointer-checks
+%ifarch armv7hl
+# gcc6: arm FTBFS
+%global qt5_arm_flag -mfpu=neon
+%endif
 %endif
 
 # define to build docs, need to undef this for bootstrapping
@@ -368,21 +376,14 @@ RPM macros for building Qt5 packages.
 %patch150 -p1 -b .moc_system_defines
 %patch176 -p1 -b .0076
 
-## adjust $RPM_OPT_FLAGS
-# remove -fexceptions
-RPM_OPT_FLAGS=`echo $RPM_OPT_FLAGS | sed 's|-fexceptions||g'`
-# add -fno-delete-null-pointer-checks for f24/gcc6
-%if 0%{?fedora} > 23
-%global qt5_rpm_opt_flags -fno-delete-null-pointer-checks -Wno-deprecated-declaration
-RPM_OPT_FLAGS="$RPM_OPT_FLAGS %{?qt5_rpm_opt_flags}"
-%ifarch armv7hl
-RPM_OPT_FLAGS="$RPM_OPT_FLAGS -mfpu=neon"
-%endif
-%endif
-
 %define platform linux-g++
 
 %if 0%{?inject_optflags}
+## adjust $RPM_OPT_FLAGS
+# remove -fexceptions
+RPM_OPT_FLAGS=`echo $RPM_OPT_FLAGS | sed 's|-fexceptions||g'`
+RPM_OPT_FLAGS="$RPM_OPT_FLAGS %{?qt5_deprecated_flag} %{?qt5_arm_flag}"
+
 %patch2 -p1 -b .multilib_optflags
 # drop backup file(s), else they get installed too, http://bugzilla.redhat.com/639463
 rm -fv mkspecs/linux-g++*/qmake.conf.multilib-optflags
@@ -423,16 +424,10 @@ test -x configure || chmod +x configure
 ## adjust $RPM_OPT_FLAGS
 # remove -fexceptions
 RPM_OPT_FLAGS=`echo $RPM_OPT_FLAGS | sed 's|-fexceptions||g'`
-# add -fno-delete-null-pointer-checks for f24/gcc6
-%if 0%{?fedora} > 23
-RPM_OPT_FLAGS="$RPM_OPT_FLAGS %{?qt5_rpm_opt_flags}"
-%ifarch armv7hl
-RPM_OPT_FLAGS="$RPM_OPT_FLAGS -mfpu=neon"
-%endif
-%endif
+RPM_OPT_FLAGS="$RPM_OPT_FLAGS %{?qt5_deprecated_flag} %{?qt5_arm_flag}"
 
 export CFLAGS="$CFLAGS $RPM_OPT_FLAGS"
-export CXXFLAGS="$CXXFLAGS $RPM_OPT_FLAGS"
+export CXXFLAGS="$CXXFLAGS $RPM_OPT_FLAGS %{?qt5_null_flag}"
 export LDFLAGS="$LDFLAGS $RPM_LD_FLAGS"
 export MAKEFLAGS="%{?_smp_mflags}"
 
@@ -550,8 +545,10 @@ sed -i \
   -e "s|@@EPOCH@@|%{?epoch}%{!?epoch:0}|g" \
   -e "s|@@VERSION@@|%{version}|g" \
   -e "s|@@EVR@@|%{?epoch:%{epoch:}}%{version}-%{release}|g" \
+  -e "s|@@QT5_CFLAGS@@|%{?qt5_cflags}|g" \
+  -e "s|@@QT5_CXXFLAGS@@|%{?qt5_null_flag}|g" \
   -e "s|@@QT5_RPM_LD_FLAGS@@|%{?qt5_rpm_ld_flags}|g" \
-  -e "s|@@QT5_RPM_OPT_FLAGS@@|%{?qt5_rpm_opt_flags}|g" \
+  -e "s|@@QT5_RPM_OPT_FLAGS@@|%{?qt5_arm_flag} %{?qt5_deprecated_flag}|g" \
   %{buildroot}%{rpm_macros_dir}/macros.qt5
 
 # create/own dirs
@@ -961,7 +958,7 @@ fi
 
 %changelog
 * Fri Mar 18 2016 Rex Dieter <rdieter@fedoraproject.org> - 5.6.0-4
-- macros.qt5: fix %%{_qt5_optflags} (for f24+)
+- macros.qt5: cleanup, %%_qt5_cflags, %%_qt5_cxxflags (for f24+)
 
 * Fri Mar 18 2016 Rex Dieter <rdieter@fedoraproject.org> - 5.6.0-3
 - rebuild