[PATCH] Add __discard section to x86

[Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>]

Add a __discard sectionto the linker script. Code produced in this section will
not be put in the vmlinux file. This is useful when we have to calculate the
size of an instruction before actually declaring it (for alignment purposes for
instance). This is used by the immediate values.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
CC: Andi Kleen <ak@muc.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Chuck Ebbert <cebbert@redhat.com>
CC: Christoph Hellwig <hch@infradead.org>
CC: Jeremy Fitzhardinge <jeremy@goop.org>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
---
 arch/x86/kernel/vmlinux_32.lds.S |    1 +
 arch/x86/kernel/vmlinux_64.lds.S |    1 +
 2 files changed, 2 insertions(+)

Index: linux-2.6-lttng/arch/x86/kernel/vmlinux_32.lds.S
===================================================================
--- linux-2.6-lttng.orig/arch/x86/kernel/vmlinux_32.lds.S	2007-11-14 14:10:43.000000000 -0500
+++ linux-2.6-lttng/arch/x86/kernel/vmlinux_32.lds.S	2007-11-14 14:11:32.000000000 -0500
@@ -205,6 +205,7 @@ SECTIONS
   /* Sections to be discarded */
   /DISCARD/ : {
 	*(.exitcall.exit)
+	*(__discard)
 	}
 
   STABS_DEBUG
Index: linux-2.6-lttng/arch/x86/kernel/vmlinux_64.lds.S
===================================================================
--- linux-2.6-lttng.orig/arch/x86/kernel/vmlinux_64.lds.S	2007-11-14 14:10:46.000000000 -0500
+++ linux-2.6-lttng/arch/x86/kernel/vmlinux_64.lds.S	2007-11-14 14:11:48.000000000 -0500
@@ -227,6 +227,7 @@ SECTIONS
   /DISCARD/ : {
 	*(.exitcall.exit)
 	*(.eh_frame)
+	*(__discard)
 	}
 
   STABS_DEBUG
-- 
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68