Commit 95272c29 authored Mar 31, 2016 by Paolo Bonzini

compiler-gcc: disable -ftracer for __noclone functions



-ftracer can duplicate asm blocks causing compilation to fail in
noclone functions.  For example, KVM declares a global variable
in an asm like

    asm("2: ... \n
         .pushsection data \n
         .global vmx_return \n
         vmx_return: .long 2b");

and -ftracer causes a double declaration.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: stable@vger.kernel.org
Cc: kvm@vger.kernel.org
Reported-by: Linda Walsh <lkml@tlinx.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 61abdbe0

include/linux/compiler-gcc.h

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -199,7 +199,7 @@
	#define unreachable() __builtin_unreachable()		#define unreachable() __builtin_unreachable()

	/* Mark a function definition as prohibited from being cloned. */		/* Mark a function definition as prohibited from being cloned. */
	#define __noclone __attribute__((__noclone__))		#define __noclone __attribute__((__noclone__, __optimize__("no-tracer")))

	#endif /* GCC_VERSION >= 40500 */		#endif /* GCC_VERSION >= 40500 */