Commit 25165120 authored Feb 22, 2007 by Ingo Molnar Committed by Linus Torvalds Feb 26, 2007

[PATCH] x86: add -freg-struct-return to CFLAGS



Jeremy Fitzhardinge suggested the use of -freg-struct-return, which does
structure-returns (such as when using pte_t) in registers instead of on
the stack.

that is indeed so, and this option reduced the kernel size a bit:

    text    data     bss     dec     hex filename
 4799506  543456 3760128 9103090  8ae6f2 vmlinux.before
 4798117  543456 3760128 9101701  8ae185 vmlinux.after

the resulting kernel booted fine on my testbox. Lets go for it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 38bed542

arch/i386/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -31,7 +31,7 @@ LDFLAGS_vmlinux := --emit-relocs
		endif
		CHECKFLAGS += -D__i386__

		CFLAGS += -pipe -msoft-float -mregparm=3
		CFLAGS += -pipe -msoft-float -mregparm=3 -freg-struct-return

		# prevent gcc from keeping the stack 16 byte aligned
		CFLAGS += $(call cc-option,-mpreferred-stack-boundary=2)

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