linux/samples/bpf/asm_goto_workaround.h
Alexei Starovoitov 636e78b1cd samples/bpf: fix build with new clang
clang started to error on invalid asm clobber usage in x86 headers
and many bpf program samples failed to build with the message:

  CLANG-bpf  /data/users/ast/bpf-next/samples/bpf/xdp_redirect_kern.o
In file included from /data/users/ast/bpf-next/samples/bpf/xdp_redirect_kern.c:14:
In file included from ../include/linux/in.h:23:
In file included from ../include/uapi/linux/in.h:24:
In file included from ../include/linux/socket.h:8:
In file included from ../include/linux/uio.h:14:
In file included from ../include/crypto/hash.h:16:
In file included from ../include/linux/crypto.h:26:
In file included from ../include/linux/uaccess.h:5:
In file included from ../include/linux/sched.h:15:
In file included from ../include/linux/sem.h:5:
In file included from ../include/uapi/linux/sem.h:5:
In file included from ../include/linux/ipc.h:9:
In file included from ../include/linux/refcount.h:72:
../arch/x86/include/asm/refcount.h:72:36: error: asm-specifier for input or output variable conflicts with asm clobber list
                                         r->refs.counter, e, "er", i, "cx");
                                                                      ^
../arch/x86/include/asm/refcount.h:86:27: error: asm-specifier for input or output variable conflicts with asm clobber list
                                         r->refs.counter, e, "cx");
                                                             ^
2 errors generated.

Override volatile() to workaround the problem.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-05 16:28:36 +02:00

18 lines
453 B
C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2019 Facebook */
#ifndef __ASM_GOTO_WORKAROUND_H
#define __ASM_GOTO_WORKAROUND_H
/* this will bring in asm_volatile_goto macro definition
* if enabled by compiler and config options.
*/
#include <linux/types.h>
#ifdef asm_volatile_goto
#undef asm_volatile_goto
#define asm_volatile_goto(x...) asm volatile("invalid use of asm_volatile_goto")
#endif
#define volatile(x...) volatile("")
#endif