echo '// SPDX-License-Identifier: GPL-2.0
/*
 * bpf-script-test-prologue.c
 * Test BPF prologue
 */
#ifndef LINUX_VERSION_CODE
# error Need LINUX_VERSION_CODE
# error Example: for 4.2 kernel, put 'clang-opt=-DLINUX_VERSION_CODE=0x40200 into llvm section of ~/.perfconfig'
#endif
#define SEC(NAME) __attribute__((section(NAME), used))

#include <uapi/linux/fs.h>

/*
 * If CONFIG_PROFILE_ALL_BRANCHES is selected,
 * 'if' is redefined after include kernel header.
 * Recover 'if' for BPF object code.
 */
#ifdef if
# undef if
#endif

#define FMODE_READ		0x1
#define FMODE_WRITE		0x2

static void (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
	(void *) 6;

SEC(func=null_lseek file- offset orig)
int bpf_func__null_lseek(void *ctx, int err, unsigned long _f_mode,
			 unsigned long offset, unsigned long orig)
{
	fmode_t f_mode = (fmode_t)_f_mode;

	if (err)
		return 0;
	if (f_mode & FMODE_WRITE)
		return 0;
	if (offset & 1)
		return 0;
	if (orig == SEEK_CUR)
		return 0;
	return 1;
}

char _license[] SEC(license) = GPL;
int _version SEC(version) = LINUX_VERSION_CODE;
' | /usr/bin/clang -D__KERNEL__ -D__NR_CPUS__=96 -DLINUX_VERSION_CODE=0x50a70 -xc  -I/root/lib/perf/include/bpf -nostdinc -isystem /usr/lib/gcc/aarch64-redhat-linux/10/include -I./arch/arm64/include -I./arch/arm64/include/generated  -I./include -I./arch/arm64/include/uapi -I./arch/arm64/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h  -Wno-unused-value -Wno-pointer-sign -working-directory /lib/modules/5.10.112-005.alpha.ali5000.alios7.aarch64/build -c - -target bpf  -O2 -o -  2>/dev/null