Index: general/prog/clisp.xml
===================================================================
--- general/prog/clisp.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ general/prog/clisp.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -113,5 +113,5 @@
 
 <screen><userinput remap="pre">case $(uname -m) in
-    i?86) export CFLAGS+=-falign-functions=4 ;;
+    i?86) export CFLAGS="${CFLAGS:--O2 -g} -falign-functions=4" ;;
 esac</userinput></screen>
 
Index: gnome/applications/evince.xml
===================================================================
--- gnome/applications/evince.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ gnome/applications/evince.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -129,6 +129,5 @@
     </para>
 
-<screen><userinput remap="pre">export CFLAGS="$CFLAGS -I/opt/texlive/&texlive-year;/include" &amp;&amp;
-export CXXFLAGS="$CXXFLAGS -I/opt/texlive/&texlive-year;/include" &amp;&amp;
+<screen><userinput remap="pre">export CPPFLAGS="-I/opt/texlive/&texlive-year;/include" &amp;&amp;
 export LDFLAGS="$LDFLAGS -L/opt/texlive/&texlive-year;/lib"</userinput></screen>
 
@@ -175,9 +174,6 @@
     -->
 
-<!-- When moving to Meson, I installed the whole texlive suite from source.
-     I was able to verify that this is no longer required. I'm assuming it was
-     one of evince-3.36.3 or texlive-2020 that fixed this.
-    <para>
-      <parameter>CFLAGS="$CFLAGS ..." CXXFLAGS="$CXXFLAGS ..." LDFLAGS="$LDFLAGS ..."</parameter>: If
+    <para>
+      <parameter>CPPFLAGS="..." LDFLAGS="$LDFLAGS ..."</parameter>: If
       <application>TeXLive</application> has been installed in
       <filename class="directory">/opt/texlive-&texlive-year;</filename> the
@@ -188,5 +184,5 @@
       build.
     </para>
--->
+
     <para>
       <parameter>-Dgtk_doc=false</parameter>: This switch disables generating
Index: multimedia/libdriv/audiofile.xml
===================================================================
--- multimedia/libdriv/audiofile.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ multimedia/libdriv/audiofile.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -103,5 +103,5 @@
     </para>
 
-<screen><userinput>CXXFLAGS=-std=c++98 \
+<screen><userinput>CXXFLAGS="${CXXFLAGS:--O2 -g} -std=c++98" \
 ./configure --prefix=/usr --disable-static &amp;&amp;
 
Index: multimedia/libdriv/liba52.xml
===================================================================
--- multimedia/libdriv/liba52.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ multimedia/libdriv/liba52.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -94,5 +94,5 @@
             --enable-shared \
             --disable-static \
-            CFLAGS="-g -O2 $([ $(uname -m) = x86_64 ] &amp;&amp; echo -fPIC)" &amp;&amp;
+            CFLAGS="${CFLAGS:--g -O2} $([ $(uname -m) = x86_64 ] &amp;&amp; echo -fPIC)" &amp;&amp;
 make</userinput></screen>
 
Index: multimedia/libdriv/libmusicbrainz.xml
===================================================================
--- multimedia/libdriv/libmusicbrainz.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ multimedia/libdriv/libmusicbrainz.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -114,5 +114,5 @@
 <screen><userinput>patch -Np1 -i ../libmusicbrainz-&libmusicbrainz-version;-missing-includes-1.patch &amp;&amp;
 
-CXXFLAGS=-std=c++98 \
+CXXFLAGS="${CXXFLAGS:--O2 -g} -std=c++98" \
 ./configure --prefix=/usr --disable-static &amp;&amp;
 make</userinput></screen>
Index: multimedia/videoutils/vlc.xml
===================================================================
--- multimedia/videoutils/vlc.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ multimedia/videoutils/vlc.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -231,7 +231,7 @@
 <!--
 <screen><userinput>sed -i '/vlc_demux.h/a #define LUA_COMPAT_APIINTCASTS' modules/lua/vlc.h   &amp;&amp;-->
-<screen><userinput>export LUAC=/usr/bin/luac5.2                 &amp;&amp;
-export LUA_LIBS="$(pkg-config --libs lua52)" &amp;&amp;
-export CFLAGS="$(pkg-config --cflags lua52)" &amp;&amp;
+<screen><userinput>export LUAC=/usr/bin/luac5.2                   &amp;&amp;
+export LUA_LIBS="$(pkg-config --libs lua52)"   &amp;&amp;
+export CPPFLAGS="$(pkg-config --cflags lua52)" &amp;&amp;
 
 BUILDCC=gcc ./configure --prefix=/usr    \
Index: networking/netprogs/ntp.xml
===================================================================
--- networking/netprogs/ntp.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ networking/netprogs/ntp.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -136,5 +136,5 @@
         Its a "hack" for gcc-10
 -->
-<screen><userinput>./configure CFLAGS="-O2 -g -fPIC -fcommon $CFLAGS" \
+<screen><userinput>./configure CFLAGS="${CFLAGS:--O2 -g} -fPIC -fcommon" \
             --prefix=/usr         \
             --bindir=/usr/sbin    \
Index: networking/netprogs/samba.xml
===================================================================
--- networking/netprogs/samba.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ networking/netprogs/samba.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -186,5 +186,5 @@
     </para>
 
-<screen revision="sysv"><userinput>CFLAGS="-I/usr/include/tirpc"          \
+<screen revision="sysv"><userinput>CPPFLAGS="-I/usr/include/tirpc"        \
 LDFLAGS="-ltirpc"                      \
 ./configure                            \
@@ -200,5 +200,5 @@
 make</userinput></screen>
 
-<screen revision="systemd"><userinput>CFLAGS="-I/usr/include/tirpc"          \
+<screen revision="systemd"><userinput>CPPFLAGS="-I/usr/include/tirpc"        \
 LDFLAGS="-ltirpc"                      \
 ./configure                            \
Index: postlfs/filesystems/sshfs.xml
===================================================================
--- postlfs/filesystems/sshfs.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ postlfs/filesystems/sshfs.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -96,15 +96,4 @@
   <sect2 role="installation">
     <title>Installation of Sshfs</title>
-    <!--
-    <para>
-      If you are building on i686, <application>sshfs</application> needs
-      an extra CFLAGS setting to be defined. This prevents an integer
-      overflow. To do this, run the following command:
-    </para>
-
-<screen><userinput>if [ $(uname -m) = "i686" ]; then
-  export CFLAGS+="-D_FILE_OFFSET_BITS=64";
-fi</userinput></screen>
-    -->
 
     <para>
Index: pst/sgml/openjade.xml
===================================================================
--- pst/sgml/openjade.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ pst/sgml/openjade.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -115,5 +115,5 @@
     </para>
 
-<screen><userinput>export CXXFLAGS="$CXXFLAGS -fno-lifetime-dse"            &amp;&amp;
+<screen><userinput>export CXXFLAGS="${CXXFLAGS:--O2 -g} -fno-lifetime-dse"            &amp;&amp;
 ./configure --prefix=/usr                                \
             --mandir=/usr/share/man                      \
Index: server/mail/dovecot.xml
===================================================================
--- server/mail/dovecot.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ server/mail/dovecot.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -135,5 +135,5 @@
     </para>
 
-<screen revision="sysv"><userinput>CFLAGS+=" -I/usr/include/tirpc" \
+<screen revision="sysv"><userinput>CPPFLAGS="-I/usr/include/tirpc" \
 LDFLAGS+=" -ltirpc" \
 ./configure --prefix=/usr                          \
@@ -145,5 +145,5 @@
 make</userinput></screen>
 
-<screen revision="systemd"><userinput>CFLAGS+=" -I/usr/include/tirpc" \
+<screen revision="systemd"><userinput>CPPFLAGS="-I/usr/include/tirpc" \
 LDFLAGS+=" -ltirpc" \
 ./configure --prefix=/usr                          \
@@ -174,5 +174,5 @@
 
     <para>
-      <command>CFLAGS+=...LDFLAGS+=...</command>: build with libtirpc
+      <command>CPPFLAGS=... LDFLAGS+=...</command>: build with libtirpc
       instead of the recently removed RPC code provided by GlibC.
     </para>
Index: x/dm/lightdm.xml
===================================================================
--- x/dm/lightdm.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ x/dm/lightdm.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -262,9 +262,4 @@
       <command>configure</command> throws an error if it is not found on the
       system. This parameter prevents the error.
-    </para>
-
-    <para>
-      <parameter>CFLAGS=...</parameter>: those two switches ensures some
-      warnings are not treated as errors.
     </para>
 
Index: x/lib/gtkmm2.xml
===================================================================
--- x/lib/gtkmm2.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ x/lib/gtkmm2.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -116,19 +116,4 @@
   </sect2>
 
-<!-- as of 2.24.5, this is no longer needed. -renodr
-  <sect2 role="commands">
-    <title>Command Explanations</title>
-
-    <para>
-      <command>CXXFLAGS="-g -O2 -std=c++11" ./configure...</command>: while
-      Gtkmm-&gtkmm2-version; has not yet been ported to the 2011 ISO C++
-      standard, all its dependencies have. <command>-std=c++11</command> has
-      to be used as an option to <command>g++</command>. We pass it into
-      <envar>CXXFLAGS</envar> together with the default options.
-    </para>
-
-  </sect2>
--->
-
   <sect2 role="content">
     <title>Contents</title>
Index: xsoft/other/thunderbird.xml
===================================================================
--- xsoft/other/thunderbird.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ xsoft/other/thunderbird.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -186,13 +186,4 @@
 ac_add_options --with-system-nss
 ac_add_options --with-system-icu
-<!--Not with libvpx-1.8.0 or later
-ac_add_options - -with-system-libvpx
-====
-These do not seem to be needed any more
-# Set CFLAGS and CXXFLAGS to prevent segfaults due to aggressive
-# optimizations in GCC-6:
-export CFLAGS+=" -fno-delete-null-pointer-checks -fno-lifetime-dse -fno-schedule-insns2"
-export CXXFLAGS+=" -fno-delete-null-pointer-checks -fno-lifetime-dse -fno-schedule-insns2"
--->
 # The elf-hack causes failed installs on some machines.
 # It is supposed to improve startup time and it shrinks libxul.so
Index: xsoft/other/tigervnc.xml
===================================================================
--- xsoft/other/tigervnc.xml	(revision 5d2965c7ff8b653e1d745e4961c3e4aab93cbce4)
+++ xsoft/other/tigervnc.xml	(revision f4302700b14fbaaa74a09b8a57906bf0474ac83f)
@@ -179,5 +179,5 @@
   autoreconf -fiv  &amp;&amp;
 
-  CFLAGS="$CFLAGS -I/usr/include/drm" \
+  CPPFLAGS="-I/usr/include/drm"       \
   ./configure $XORG_CONFIG            \
       --disable-xwayland    --disable-dri        --disable-dmx         \
