[PATCH/RFC] doc/install.texi: clarify that --with-arch etc apply to the build of gcc, too

[Jonathan Nieder <jrnieder at gmail dot com>]

Hi,

Someone on IRC was having trouble getting a build after
./configure --with-tune=athlon64-sse3 to proceed without errors.  So I
wondered what --with-tune actually does.  The current documentation
does not make it clear whether this option affects the optimization of
the gcc binary itself.  Does it?

If yes, perhaps something like the following would make this more
clear.  If no, please let me know and I can write a patch indicating
the opposite.

Also, thank you for rearing gcc to be the well behaved package it is.

Sincerely,
Jonathan

2010-01-18  Jonathan Nieder  <jrnieder@gmail.com>

	* doc/install.texi (Configuration#Options specification): Clarify
	that defaults set by --with-{schedule,arch,tune,abi,fpu,float}
	also apply to the optimization of the stage2 and stage3 compilers.

diff --git r155999/doc/install.texi b/doc/install.texi
index 18b29a5..51a2015 100644
--- r155999/doc/install.texi
+++ b/doc/install.texi
@@ -1162,9 +1162,11 @@ x86-64 and PowerPC.
 @itemx --with-float=@var{type}
 These configure options provide default values for the @option{-mschedule=},
 @option{-march=}, @option{-mtune=}, @option{-mabi=}, and @option{-mfpu=}
-options and for @option{-mhard-float} or @option{-msoft-float}.  As with
-@option{--with-cpu}, which switches will be accepted and acceptable values
-of the arguments depend on the target.
+options and for @option{-mhard-float} or @option{-msoft-float}.  In native
+builds, these flags are used to build gcc as well as acting as defaults for
+optimization of programs built with it.  As with @option{--with-cpu}, which
+switches will be accepted and acceptable values of the arguments depend on
+the target.
 
 @item --with-mode=@var{mode}
 Specify if the compiler should default to @option{-marm} or @option{-mthumb}.
diff --git r155999/ChangeLog b/ChangeLog
index a518cfd..d116680 100644
--- r155999/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2010-01-18  Jonathan Nieder  <jrnieder@gmail.com>
+
+	* doc/install.texi (Configuration#Options specification): Clarify
+	that defaults set by --with-{schedule,arch,tune,abi,fpu,float}
+	also apply to the optimization of the stage2 and stage3 compilers.
+
 2010-01-18  Joern Rennecke  <amylaar@spamcop.net>
 
 	* doc/tm.texi (TARGET_ASM_FUNCTION_EPILOGUE): Update text on where to