如何通过 zig builed-exec 生成 armv5 二进制文件

Question

主机

这是目标系统中正在运行的二进制文件

readelf -h asterisk

ELF Header:
  Magic:   7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
  Class:                             ELF32
  Data:                              2's complement, little endian
  Version:                           1 (current)
  OS/ABI:                            UNIX - System V
  ABI Version:                       0
  Type:                              EXEC (Executable file)
  Machine:                           ARM
  Version:                           0x1
  Entry point address:               0x1ee30
  Start of program headers:          52 (bytes into file)
  Start of section headers:          3431360 (bytes into file)
  Flags:                             0x4000002, Version4 EABI, <unknown>
  Size of this header:               52 (bytes)
  Size of program headers:           32 (bytes)
  Number of program headers:         8
  Size of section headers:           40 (bytes)
  Number of section headers:         27
  Section header string table index: 26

目标系统 cpu 信息

Processor   : ARMv6-compatible processor rev 5 (v6l)
BogoMIPS    : 648.80
Features    : swp half thumb fastmult edsp java
CPU implementer : 0x41
CPU architecture: 6TEJ
CPU variant : 0x1
CPU part    : 0xb36
CPU revision    : 5

Hardware    : Comcerto 1000 (EVM)
Revision    : 0000
Serial      : 0000000000000000

dmesg 信息

dmesg | head

Initializing cgroup subsys cpuset
Initializing cgroup subsys cpu
Linux version 2.6.33.5 ([email protected]) (gcc version 4.1.2) #5 Mon Jan 29 20:07:16 CST 2018
CPU: ARMv6-compatible processor [4117b365] revision 5 (ARMv6TEJ), cr=00c5387d
CPU: VIPT aliasing data cache, VIPT aliasing instruction cache
Machine: Comcerto 1000 (EVM)
Memory policy: ECC disabled, Data cache writeback
On node 0 totalpages: 30720
free_area_init_node: node 0, pgdat c0399e54, node_mem_map c03c2000
  DMA zone: 240 pages used for memmap

zig build-exec

进行构建

# running ./hello Aborted
zig build-exe -target arm-linux-none -mcpu=arm1136j_s hello.zig
# Aborted
zig build-exe -target arm-linux-eabi -mcpu=arm1136j_s hello.zig
# Illegal instruction
zig build-exe -target arm-linux-eabi hello.zig

尝试使用 v4 和 v4 v5 mcpu，但构建失败

• arm710t
• arm1020e
• arm1020t
• arm1022e

ld.lld: warning: lld uses blx instruction, no object with architecture supporting feature detected
ld.lld: error: undefined symbol: __sync_val_compare_and_swap_4
>>> referenced by heap.zig:352 (/usr/lib/zig/std/heap.zig:352)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.heap.PageAllocator.alloc)
>>> referenced by Mutex.zig:101 (/usr/lib/zig/std/Thread/Mutex.zig:101)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.Thread.Mutex.AtomicMutex.lockSlow)
>>> referenced by StaticResetEvent.zig:149 (/usr/lib/zig/std/Thread/StaticResetEvent.zig:149)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.Thread.StaticResetEvent.AtomicEvent.timedWait)
>>> referenced 2 more times

ld.lld: error: undefined symbol: __sync_fetch_and_add_1
>>> referenced by debug.zig:284 (/usr/lib/zig/std/debug.zig:284)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.debug.panicImpl)

ld.lld: error: undefined symbol: __sync_fetch_and_sub_1
>>> referenced by debug.zig:305 (/usr/lib/zig/std/debug.zig:305)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.debug.panicImpl)

ld.lld: error: undefined symbol: __sync_lock_test_and_set_4
>>> referenced by Mutex.zig:81 (/usr/lib/zig/std/Thread/Mutex.zig:81)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.Thread.Mutex.AtomicMutex.lock)
>>> referenced by Mutex.zig:88 (/usr/lib/zig/std/Thread/Mutex.zig:88)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.Thread.Mutex.AtomicMutex.unlock)
>>> referenced by Mutex.zig:123 (/usr/lib/zig/std/Thread/Mutex.zig:123)
>>>               zig-cache/o/750724e51d9b1b9d610b91ec3f30a585/hello.o:(std.Thread.Mutex.AtomicMutex.lockSlow)
error: LLDReportedFailure

---

但是交叉构建可以在目标中运行

# produce EABI5 & armv5
GOOS=linux GOARM=5 GOARCH=arm CGO_ENABLED=0 go build hello.go

所以我猜问题是zig产生EABI5或armv6，但是armv5 mcpu没有可以通过构建，我该怎么办使用 zig 生成 EABI4 或 armv5 二进制文件？

相关 PR

• https://github.com/ziglang/zig/pull /10756