在越狱的 iOS 上使用 ar 或 libtool 创建静态档案失败

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我正在尝试在自托管的越狱 ios 设备（corellium 虚拟设备）上构建并运行 go。 go bootstraps，可以构建和运行常规二进制文件。但是，go 档案无法构建，因为 ar 不起作用：

$ dpkg -s /usr/bin/clang /usr/bin/ar /usr/bin/libtool
org.coolstar.llvm-clang64: /usr/bin/clang
org.coolstar.cctools: /usr/bin/ar
org.coolstar.cctools: /usr/bin/libtool
$ apt policy org.coolstar.cctools org.coolstar.llvm-clang64
org.coolstar.cctools:
  installed: 895
  candidate: 895
  version table:
 *** 895 500
        500 http://apt.thebigboss.org/repofiles/cydia stable/main iphoneos-arm packages
        100 /library/dpkg/status
org.coolstar.llvm-clang64:
  installed: 5.0.1-2
  candidate: 5.0.1-2
  version table:
 *** 5.0.1-2 500
        500 http://apt.thebigboss.org/repofiles/cydia stable/main iphoneos-arm packages
        100 /library/dpkg/status

$ ../bin/go build -buildmode=c-archive -ldflags="-v" -work ../misc/ios/detect.go
work=/tmp/go-build734936238
# command-line-arguments
header = -h1 -t0x2000 -r0x1000
 0.00 deadcode
 0.05 symsize = 0
 0.08 pclntab=740717 bytes, funcdata total 185492 bytes
 0.08 dodata
 0.08 symsize = 0
 0.08 symsize = 0
 0.09 dynreloc
 0.09 dwarf
 0.12 asmb
 0.13 datblk
 0.14 reloc
 0.20 sym
 0.22 header
archive: ar -q -c -s $work/b001/exe/a.out.a /tmp/go-link-569975294/go.o /tmp/go-link-569975294/000000.o /tmp/go-link-569975294/000001.o /tmp/go-link-569975294/000002.o /tmp/go-link-569975294/000003.o /tmp/go-link-569975294/000004.o /tmp/go-link-569975294/000005.o /tmp/go-link-569975294/000006.o /tmp/go-link-569975294/000007.o /tmp/go-link-569975294/000008.o /tmp/go-link-569975294/000009.o /tmp/go-link-569975294/000010.o /tmp/go-link-569975294/000011.o /tmp/go-link-569975294/000012.o /tmp/go-link-569975294/000013.o /tmp/go-link-569975294/000014.o
/var/mobile/go-tip/pkg/tool/darwin_arm64/link: running ar failed: exit status 1
fatal error: ar: can't find or exec: /usr/bin/arm64-apple-darwin14-ranlib (no such file or directory)
ar: internal ranlib command failed

尽管我很乐观，但我尝试了符号链接 ranlib：

# ln -s /usr/bin/ranlib /usr/bin/arm64-apple-darwin14-ranlib
$ ../bin/go build -buildmode=c-archive -ldflags="-v" -work ../misc/ios/detect.go
work=/tmp/go-build239621581
# command-line-arguments
header = -h1 -t0x2000 -r0x1000
 0.00 deadcode
 0.06 symsize = 0
 0.08 pclntab=740717 bytes, funcdata total 185492 bytes
 0.08 dodata
 0.09 symsize = 0
 0.09 symsize = 0
 0.09 dynreloc
 0.10 dwarf
 0.12 asmb
 0.13 datblk
 0.15 reloc
 0.20 sym
 0.22 header
archive: ar -q -c -s $work/b001/exe/a.out.a /tmp/go-link-618780113/go.o /tmp/go-link-618780113/000000.o /tmp/go-link-618780113/000001.o /tmp/go-link-618780113/000002.o /tmp/go-link-618780113/000003.o /tmp/go-link-618780113/000004.o /tmp/go-link-618780113/000005.o /tmp/go-link-618780113/000006.o /tmp/go-link-618780113/000007.o /tmp/go-link-618780113/000008.o /tmp/go-link-618780113/000009.o /tmp/go-link-618780113/000010.o /tmp/go-link-618780113/000011.o /tmp/go-link-618780113/000012.o /tmp/go-link-618780113/000013.o /tmp/go-link-618780113/000014.o
/var/mobile/go-tip/pkg/tool/darwin_arm64/link: running ar failed: exit status 1
/usr/bin/arm64-apple-darwin14-ranlib: archive member: $work/b001/exe/a.out.a(go.o) offset in archive not a multiple of 8 (must be since member is an 64-bit object file)
fatal error: ar: fatal error in /usr/bin/arm64-apple-darwin14-ranlib

我什至将 go 切换为使用 libtool：

$ ../bin/go build -buildmode=c-archive -ldflags="-v" -work ../misc/ios/detect.go
work=/tmp/go-build502332895
# command-line-arguments
header = -h1 -t0x2000 -r0x1000
 0.00 deadcode
 0.04 symsize = 0
 0.08 pclntab=740717 bytes, funcdata total 185492 bytes
 0.08 dodata
 0.08 symsize = 0
 0.09 symsize = 0
 0.09 dynreloc
 0.10 dwarf
 0.12 asmb
 0.14 datblk
 0.15 reloc
 0.20 sym
 0.22 header
archive: libtool -static -o $work/b001/exe/a.out.a /tmp/go-link-320669019/go.o /tmp/go-link-320669019/000000.o /tmp/go-link-320669019/000001.o /tmp/go-link-320669019/000002.o /tmp/go-link-320669019/000003.o /tmp/go-link-320669019/000004.o /tmp/go-link-320669019/000005.o /tmp/go-link-320669019/000006.o /tmp/go-link-320669019/000007.o /tmp/go-link-320669019/000008.o /tmp/go-link-320669019/000009.o /tmp/go-link-320669019/000010.o /tmp/go-link-320669019/000011.o /tmp/go-link-320669019/000012.o /tmp/go-link-320669019/000013.o /tmp/go-link-320669019/000014.o
/var/mobile/go-tip/pkg/tool/darwin_arm64/link: running libtool failed: signal: segmentation fault

现在，ar（带有符号链接的 ranlib）即使在简单的目标文件上也会失败：

$ cat blah.c
int blah() {
    return 0;
}
$ clang -c blah.c
$ ar -q -c -s blah.a blah.o
/usr/bin/arm64-apple-darwin14-ranlib: archive member: blah.a(blah.o) offset in archive not a multiple of 8 (must be since member is an 64-bit object file)

libtool 的工作原理：

$ libtool -static -o blah.a blah.o

但如上所示，更复杂的目标文件上会出现段错误。

go 已经可以使用 xcode ar 工具成功创建档案。只有 ios 原生“cctools”版本失败。

解决方案

我使用 llvm-ar 解决了这个问题。命令行标志略有不同，但至少我现在有一个工作存档。

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