--- make.conf	2006-03-19 18:40:11.000000000 +0100
+++ make.conf.ppc	2006-03-19 18:26:21.000000000 +0100
@@ -23,6 +23,13 @@
 # Example:
 #USE="X gtk gnome -alsa"
 
+# Host Setting
+# ============
+#
+# All PowerPC systems should use this host setting:
+
+CHOST="powerpc-unknown-linux-gnu"
+
 # Host and optimization settings 
 # ==============================
 #
@@ -33,10 +40,56 @@
 # package (and in some cases the libraries it uses) at default optimizations
 # before reporting errors to developers.
 #
-# Please refer to the GCC manual for a list of possible values.
+# -mcpu=<cpu-type> for PowerPC systems selects the type of processor you want
+# to optimize your code for.   Code generated under those options will run best
+# on that processor, and may not run at all on others.
+#
+# GCC 3.4 supports many powerpc processor types including: 401, 403, 405,
+# 405fp, 440, 440fp, 505, 601, 602, 603, 603e, 604, 604e, 620, 630, 740, 7400,
+# 7450, 750, 801, 821, 823, 860, 970, 8540, common, ec603e, G3, G4, G5, power,
+# power2, power3, power4, power5, powerpc, powerpc64, rios, rios1, rios2, rsc,
+# and rs64a
+#
+# Recommended settings for GCC 3.4 only :
+#
+# -maltivec enables optional altivec support and should be used
+# only for G4 processors,  on GCC 3.2 or newer.  It also requires that you have
+# the alitvec option compiled into your kernel to take full advantage of this
+# feature.  Note: you should also include -mabi=altivec flag if using this 
+# option.
+#
+# The newer gcc has a stricter aliasing ruleset that makes type punned 
+# expression faulty compiled if -fstrict-aliasing is enabled.
+# That option is implied by -O2 -Os and -O3. Make SURE you don't have that
+# option enabled by adding -fno-strict-aliasing to your CFLAGS and CXXFLAGS
+#
+# Long term testing has shown that -O3 opts can be unreliable on G4's but work
+# on G3 series processors or earlier.
+#
+# The following is the suggested CFLAGS for a generic G4 cpu
+#
+#CFLAGS="-O2 -pipe -mcpu=G4 -maltivec -mabi=altivec -fno-strict-aliasing"
 #
-#CFLAGS="-O2 -pipe"
 #
+# All non G4 PPC boxen should choose this next option.  It will work fine for
+# all G3 and pre machines.  (note it will not hurt pre G3 machines either to 
+# use this mcpu option as it is the default for gcc 3.2.x anyway)
+#
+#CFLAGS="-O2 -pipe -mcpu=G3 -fno-strict-aliasing"
+
+# Recommended settings for GCC 2.95.3 only (Gentoo 1.2 or older):
+#
+# PowerPC 750 > up: this works on G3's and G4s, gcc 2.95.3 doesn't make the
+# distinction between G3 and G4, so this is fine for all NewWorld machines, if
+# you use yaboot to boot you should select this option
+#
+#CFLAGS="-O2 -pipe -mcpu=750 -mpowerpc-gfxopt -mmultiple -mstring"
+#
+# This will run on all other processors, by building more generic code This is
+# safe for all PPC machines running gcc 2.95.3, and works for all OldWorld
+# machines - if you use BootX to boot you should select this option
+#CFLAGS="-O2 -pipe -mmultiple -mstring"
+
 # If you set a CFLAGS above, then this line will set your default C++ flags to
 # the same settings.
 #CXXFLAGS="${CFLAGS}"
@@ -61,7 +114,10 @@
 # DO NOT PUT ANYTHING BUT YOUR SPECIFIC ~ARCHITECTURE IN THE LIST.
 # IF YOU ARE UNSURE OF YOUR ARCH, OR THE IMPLICATIONS, DO NOT MODIFY THIS.
 #
-#ACCEPT_KEYWORDS="~arch"
+# Note: this really shouldn't be enabled until _AFTER_ you bootstrap and emerge
+# system.  If you want the testing things update after these steps are completed.
+#
+#ACCEPT_KEYWORDS="~ppc"
 
 # Portage Directories
 # ===================