re PR target/47643 (x86 -mtune docs still imply i386 is the default for codegen)

	PR target/47643
	* doc/invoke.texi (i386 and x86-64 Options): Fix description of
	-mtune without -march.

From-SVN: r182630

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3c785e1ce460e8e618340af1ab6a5618306ff248..4788efa5c8342fe3f94a8f2ed53ceff9ac0f140f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2011-12-22  Jonathan Wakely  <jwakely.gcc@gmail.com>
+
+       PR target/47643
+       * doc/invoke.texi (i386 and x86-64 Options): Fix description of
+       -mtune without -march.
+
 2011-12-21  Richard Earnshaw  <rearnsha@arm.com>
 
        PR target/51643

diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 99427553edccef4a50327b84cba9e90b5ad4b3aa..c779d27428fb9df8059e9628d683f097ef7ad3a8 100644 (file)
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -12847,8 +12847,10 @@ Embedded AMD CPU with MMX and 3DNow!@: instruction set support.
 
 While picking a specific @var{cpu-type} will schedule things appropriately
 for that particular chip, the compiler will not generate any code that
-does not run on the i386 without the @option{-march=@var{cpu-type}} option
-being used.
+does not run on the default machine type without the @option{-march=@var{cpu-type}}
+option being used. For example, if GCC is configured for i686-pc-linux-gnu
+then @option{-mtune=pentium4} will generate code that is tuned for Pentium4
+but will still run on i686 machines.
 
 @item -march=@var{cpu-type}
 @opindex march