`configure` 脚本无法构建 `.so` 动态库，但 `xmake f -k shared` 可以

[mochaaP]

描述问题

https://github.com/tboox/tbox/blob/master/src/tbox/xmake.sh?plain=1#L4

static 改为 shared 后：

linking.release build/linux/x86_64/release/libtbox.so
/usr/bin/ld: build/.objs/tbox/linux/x86_64/release/src/tbox/math/fixed16.c.o: relocation R_X86_64_32S against `.rodata' can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: failed to set dynamic section sizes: bad value
collect2: error: ld returned 1 exit status
make: *** [makefile:46: build/linux/x86_64/release/libtbox.so] Error 1

期待的结果

与 xmake f -k shared && xmake b 相同：

[ 99%]: linking.release libtbox.so
[100%]: build ok, spent 4.317s

相关环境

gcc (GCC) 13.1.1 20230614 (Red Hat 13.1.1-4)
Copyright (C) 2023 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

GNU ld version 2.40-9.fc39
Copyright (C) 2023 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) a later version.
This program has absolutely no warranty.

其他信息

请提供其他附加信息帮助我们诊断问题。

[waruqi]

tbox 应该还不支持动态库，xmake.lua 里面是走了 xmake 自动全量导出符号的，xmake 帮忙做了很多事情在里面，configure 是精简版，目前是不支持的，只能构建静态 tbox 库 ，建议使用静态库版本

[topazus]

I think we can package tbox as static library, though the Fedora packaging guidelines said that it is should be avoided as possible. Maybe later when xmake is packaged in Fedora repository, so it can attempt to use xmake to build tbox as shared library?

Ref: https://docs.fedoraproject.org/en-US/packaging-guidelines/#_packaging_static_libraries

[waruqi]

I have support shared library for xmake.sh

./configure --kind=shared
make

[mochaaP]

cflags 需要添加 -fPIC

diff --git a/src/xmake.sh b/src/xmake.sh
index f6fea02c..3d7c7440 100755
--- a/src/xmake.sh
+++ b/src/xmake.sh
@@ -22,6 +22,8 @@ else
     set_strip "all"
     if ! is_kind "shared"; then
         set_symbols "hidden"
+    elif is_kind "shared"; then
+        add_cxflags "-fPIC"
     fi
     set_optimizes "smallest"
 fi

[waruqi]

试下 应该可以了

[topazus]

For the building of shared library, it needs to be set soname versioning.

[mochaaP]

@topazus:
I doubt that tbox have a stable or versioned ABI?

[mochaaP]

@waruqi

Considering adding -Wl,-soname,libtbox.so.{major}(.{minor}) to linker flags?

[waruqi]

-Wl,-soname,libtbox.so.{major}(.{minor})

这有点跟系统平台相关了，这边不太好内置添加，也许其他发行版不是约定的这种 soname 格式呢，例如有可能是 libtbox.1.7.so 呢。。没有统一的规范，像 android 上通常也只需要 libtbox.so 不需要加版本。。

要么你们加个 patch ，仅仅对 fedora 处理这个。

    if is_kind "shared"; then
        add_shflags "-Wl,-soname,libtbox.so.1.7"
    fi

[mochaaP]

其實是統一的，DT_SONAME 這個字段在 Android 上也是有相同語義的。

https://en.wikipedia.org/wiki/Soname

[waruqi]

https://en.wikipedia.org/wiki/Soname

但是通常构建的 jni so 库，对 app 加载来讲，是不需要这个的，也不需要加版本，我说的不是 android 系统库

另外 macos 上又是 libtbox.1.7.3.dylib ，又不同

[mochaaP]

DT_SONAME 不影響你 dlopen() 時的實際名字啊。你最終成品如果生成 libtbox.so 也沒問題的。
只要頭裡有這個信息就好了，symlink 什麼的 rpm 這邊會自動搞定。

另外 macos 上又是 libtbox.1.7.3.dylib ，又不同

那就 libtbox.so.x.y.z 也可以