Re: [PATCH for review] [67/145] x86_64: Detect CFI support in the assembler at runtime

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Aug 11, 2006 at 07:55:58AM +0200, Andi Kleen wrote:
> On Friday 11 August 2006 07:39, Sam Ravnborg wrote:
> > > +# as-instr
> > > +# Usage: cflags-y += $(call as-instr, instr, option1, option2)
> > > +
> > > +as-instr = $(shell if echo -e "$(1)" | $(AS) -Z -o /dev/null \
> > > +		   2>&1 >/dev/null ; then echo "$(2)"; else echo "$(3)"; fi;)
> > 
> > Have you checked that as will not delete yout /dev/null if you build as
> > root? ld do so if you specify /dev/null as output file.
> 
> No. But it's probably safter to do it otherwise. Do you have an alternative?

ld-option uses this:
# ld-option
# Usage: ldflags += $(call ld-option, -Wl$(comma)--hash-style=both)
ld-option = $(shell if $(CC) $(1) \
                       -nostdlib -o ldtest$$$$.out -xc /dev/null \
             > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi; \
             rm -f ldtest$$$$.out)

$$$$ becomes $$ when executed.

I have no better alternatives - except maybe for mktemp.

	Sam
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux