当我编译以下代码片段(playground link)时:
package main
/*
#cgo LDFLAGS: -lbluetooth
#include <bluetooth/bluetooth.h>
#include <bluetooth/hci.h>
#include <bluetooth/hci_lib.h>
*/
import "C"
func main() {
C.hci_get_route(nil)
}
...使用这些环境变量:
CC=arm-linux-gnueabihf-gcc
CGO_ENABLED=1
GOARCH=arm
GOARM=6
我得到一个1.6Mb的二进制文件:
当我在Pi上运行它时,我得到一个“Segmentation fault
”。
当我使用这些环境变量运行它时:
LD_PRELOAD=/lib/arm-linux-gnueabihf/libSegFault.so
SEGFAULT_USE_ALTSTACK=1
我得到了这个输出:
*** Segmentation fault
Register dump:
R0: 00000000 R1: 00000001 R2: bebf37f4 R3: bebf37fc
R4: 00000000 R5: 00000000 R6: 00010c59 R7: 00000000
R8: 00000000 R9: 00000000 SL: b6f33000 FP: 00000000
IP: 0000004f SP: bebf37ec LR: 00010c6b PC: 0005d7f4
CPSR: 40000030
Trap: 0000000e Error: 00000817 OldMask: 00000000
Addr: 00000001
Backtrace:
Memory map:
00010000-00125000 r-xp 00000000 b3:02 16193 /home/pi/test
00135000-0013b000 rw-p 00115000 b3:02 16193 /home/pi/test
0013b000-0014a000 rw-p 00000000 00:00 0
0026b000-00290000 rw-p 00000000 00:00 0 [heap]
b6d53000-b6d73000 r-xp 00000000 b3:02 16080 /lib/arm-linux-gnueabihf/libgcc_s.so.1
b6d73000-b6d7a000 ---p 00020000 b3:02 16080 /lib/arm-linux-gnueabihf/libgcc_s.so.1
b6d7a000-b6d7b000 rw-p 0001f000 b3:02 16080 /lib/arm-linux-gnueabihf/libgcc_s.so.1
b6d7b000-b6e9f000 r-xp 00000000 b3:02 4254 /lib/arm-linux-gnueabihf/libc-2.13.so
b6e9f000-b6ea6000 ---p 00124000 b3:02 4254 /lib/arm-linux-gnueabihf/libc-2.13.so
b6ea6000-b6ea8000 r--p 00123000 b3:02 4254 /lib/arm-linux-gnueabihf/libc-2.13.so
b6ea8000-b6ea9000 rw-p 00125000 b3:02 4254 /lib/arm-linux-gnueabihf/libc-2.13.so
b6ea9000-b6eac000 rw-p 00000000 00:00 0
b6eac000-b6ec0000 r-xp 00000000 b3:02 4247 /lib/arm-linux-gnueabihf/libpthread-2.13.so
b6ec0000-b6ec7000 ---p 00014000 b3:02 4247 /lib/arm-linux-gnueabihf/libpthread-2.13.so
b6ec7000-b6ec8000 r--p 00013000 b3:02 4247 /lib/arm-linux-gnueabihf/libpthread-2.13.so
b6ec8000-b6ec9000 rw-p 00014000 b3:02 4247 /lib/arm-linux-gnueabihf/libpthread-2.13.so
b6ec9000-b6ecb000 rw-p 00000000 00:00 0
b6ecb000-b6ee0000 r-xp 00000000 b3:02 44311 /usr/lib/arm-linux-gnueabihf/libbluetooth.so.3.12.0
b6ee0000-b6ee7000 ---p 00015000 b3:02 44311 /usr/lib/arm-linux-gnueabihf/libbluetooth.so.3.12.0
b6ee7000-b6ee8000 r--p 00014000 b3:02 44311 /usr/lib/arm-linux-gnueabihf/libbluetooth.so.3.12.0
b6ee8000-b6eea000 rw-p 00015000 b3:02 44311 /usr/lib/arm-linux-gnueabihf/libbluetooth.so.3.12.0
b6ef8000-b6efa000 r-xp 00000000 b3:02 25761 /usr/lib/arm-linux-gnueabihf/libcofi_rpi.so
b6efa000-b6f01000 ---p 00002000 b3:02 25761 /usr/lib/arm-linux-gnueabihf/libcofi_rpi.so
b6f01000-b6f02000 rw-p 00001000 b3:02 25761 /usr/lib/arm-linux-gnueabihf/libcofi_rpi.so
b6f02000-b6f04000 r-xp 00000000 b3:02 4246 /lib/arm-linux-gnueabihf/libSegFault.so
b6f04000-b6f0b000 ---p 00002000 b3:02 4246 /lib/arm-linux-gnueabihf/libSegFault.so
b6f0b000-b6f0c000 r--p 00001000 b3:02 4246 /lib/arm-linux-gnueabihf/libSegFault.so
b6f0c000-b6f0d000 rw-p 00002000 b3:02 4246 /lib/arm-linux-gnueabihf/libSegFault.so
b6f0d000-b6f2a000 r-xp 00000000 b3:02 4248 /lib/arm-linux-gnueabihf/ld-2.13.so
b6f2e000-b6f32000 rw-p 00000000 00:00 0
b6f32000-b6f33000 r--p 0001d000 b3:02 4248 /lib/arm-linux-gnueabihf/ld-2.13.so
b6f33000-b6f34000 rw-p 0001e000 b3:02 4248 /lib/arm-linux-gnueabihf/ld-2.13.so
bebd3000-bebf4000 rw-p 00000000 00:00 0
bee7f000-bee80000 r-xp 00000000 00:00 0 [sigpage]
ffff0000-ffff1000 r-xp 00000000 00:00 0 [vectors]
Segmentation fault
从/usr/lib/arm-linux-gnueabihf/libcofi_rpi.so
删除/etc/ld.so.preload
会给我相同的输出,除非没有包含libcofi_rpi.so
的行。
尝试使用-tags netgo -a -ldflags "-linkmode external -extldflags -static"
构建静态链接的二进制文件,为我提供了“Illegal instruction
”而不是“Segmentation fault
”。
尝试在Pi本身上构建二进制文件是有效的,但是,我想交叉编译它。交叉编译确实有效,但仅限于ODROID-C1 / Arch,而不是Raspberry Pi / Raspbian。
我使用的确切构建步骤可以使用Docker重现:
$ docker run -it golang:1.4.1-cross bash
在docker中,我运行:
echo "deb http://emdebian.org/tools/debian/ jessie main" >/etc/apt/sources.list.d/crosstools.list
curl -s http://emdebian.org/tools/debian/emdebian-toolchain-archive.key | apt-key add -
dpkg --add-architecture armhf
apt-get update
apt-get install -y crossbuild-essential-armhf libbluetooth-dev:armhf
export CC=arm-linux-gnueabihf-gcc
export CGO_ENABLED=1
export GOARCH=arm
export GOARM=6
go build -o test test.go
这给了我一个名为“test”的可执行文件,如上所述,它不会在Pi上运行。
以下是有关我的测试设备的一些信息:
$ uname -a
Linux raspberrypi 3.18.5+ #744 PREEMPT Fri Jan 30 18:19:07 GMT 2015 armv6l GNU/Linux
$ cat /proc/cpuinfo
processor : 0
model name : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS : 2.00
Features : half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xb76
CPU revision : 7
Hardware : BCM2708
Revision : 0010
Serial : 000000002a69d702
$ ldd test
/usr/lib/arm-linux-gnueabihf/libcofi_rpi.so (0xb6f01000)
libbluetooth.so.3 => /usr/lib/arm-linux-gnueabihf/libbluetooth.so.3 (0xb6ed4000)
libpthread.so.0 => /lib/arm-linux-gnueabihf/libpthread.so.0 (0xb6eb5000)
libc.so.6 => /lib/arm-linux-gnueabihf/libc.so.6 (0xb6d84000)
/lib/ld-linux-armhf.so.3 (0xb6f0e000)
已安装的蓝牙库:
$ dpkg -s libbluetooth3
Package: libbluetooth3
Status: install ok installed
Priority: optional
Section: libs
Installed-Size: 172
Maintainer: Debian Bluetooth Maintainers <pkg-bluetooth-maintainers@lists.alioth.debian.org>
Architecture: armhf
Multi-Arch: same
Source: bluez
Version: 4.99-2
Replaces: libsdp2 (<= 1.5-2)
Depends: libc6 (>= 2.13-28)
Pre-Depends: multiarch-support
Conflicts: libsdp2 (<= 1.5-2)
Description: Library to use the BlueZ Linux Bluetooth stack
BlueZ is the official Linux Bluetooth protocol stack. It is an Open Source
project distributed under GNU General Public License (GPL).
Homepage: http://www.bluez.org
$ uname -a
Linux alarm 3.10.66-1-ARCH #1 SMP PREEMPT Wed Jan 28 18:12:35 MST 2015 armv7l GNU/Linux
$ cat /proc/cpuinfo
Processor : ARMv7 Processor rev 1 (v7l)
processor : 0
BogoMIPS : 3.27
processor : 1
BogoMIPS : 3.27
processor : 2
BogoMIPS : 3.27
processor : 3
BogoMIPS : 3.27
Features : swp half thumb fastmult vfp edsp neon vfpv3 tls vfpv4
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xc05
CPU revision : 1
Hardware : ODROIDC
Revision : 000a
Serial : 1b00000000000000
$ ldd test
libbluetooth.so.3 => /usr/lib/libbluetooth.so.3 (0xb6eaf000)
libpthread.so.0 => /usr/lib/libpthread.so.0 (0xb6e87000)
libc.so.6 => /usr/lib/libc.so.6 (0xb6d48000)
/lib/ld-linux-armhf.so.3 (0xb6ed1000)
已安装的蓝牙库&amp;开发头文件:
$ pacman -Qe bluez
bluez 5.27-1
$ uname -a
Linux 094aa2ed34a5 3.18.5-gentoo-tp #1 SMP Fri Feb 6 20:14:55 CET 2015 x86_64 GNU/Linux
已安装的蓝牙开发标题:
$ dpkg -s libbluetooth-dev:armhf
Package: libbluetooth-dev
Status: install ok installed
Priority: extra
Section: libdevel
Installed-Size: 429
Maintainer: Debian Bluetooth Maintainers <pkg-bluetooth-maintainers@lists.alioth.debian.org>
Architecture: armhf
Source: bluez (5.23-2)
Version: 5.23-2+b1
Replaces: libsdp2-dev (<= 1.5.2)
Provides: libbluetooth3-dev
Depends: libbluetooth3 (= 5.23-2+b1), libc6-dev | libc-dev
Suggests: pkg-config
Conflicts: bluez-pan, libbluetooth-dev, libsdp2-dev (<= 1.5.2)
Description: Development files for using the BlueZ Linux Bluetooth library
BlueZ is the official Linux Bluetooth protocol stack. It is an Open Source
project distributed under GNU General Public License (GPL).
Homepage: http://www.bluez.org
在Docker容器中安装完全相同版本的libbluetooth-dev
,因为Pi上可用的版本没有区别。
将较新的libbluetooth.so
从Jessie复制到Wheezie会给我这个错误:
./test: /lib/arm-linux-gnueabihf/libc.so.6: version `GLIBC_2.15' not found (required by /home/pi/libbluetooth.so.3.17.11)
在Pi上尝试使用Arch,交叉编译的二进制文件也是段错误,使用Illegal instruction (core dumped)
,GOARM=5
或6
给出相同的消息(“7
”)。< / p>
到目前为止,我还没有找到一种方法来交叉编译Pi的CGO代码,与libbluetooth
链接。
明天将尝试使用Raspberry Pi 2.
答案 0 :(得分:0)
所以,让我回答一下我自己的问题,经过数周的试验和错误后得出结论......
作为最后的手段,我尝试使用与编译上述代码完全相同的Raspbian图像,并使用QEMU 运行它。猜猜看:我遇到了一个段错误。使用相同图像的相同指令在我在Pi上运行时给了我一个可执行的可执行文件,在我模拟Pi或尝试以任何方式交叉编译它时发生了段错误。
最后,这不值得麻烦。我们只是设置了专门的Pi来构建我们的项目,而“生产”Pis只需要更新二进制文件。