上下文：我可以创建一个链接到静态库的共享对象库,在32位
linux上没有任何问题.当我在64位linux上尝试相同的构建时,我看到这个链接器错误：
在制作共享对象时,不能使用>对本地符号的重定位R_X86_64_32S;用-fPIC重新编译
这个错误在网络上很常见.解决方案是使用位置无关代码(-fPIC)编译静态链接库.
我不明白为什么32bit版本不需要这个.任何人都可以帮忙吗？
解决方法
如果您的目标模块将在共享库中使用,则始终需要“位置无关代码”.它依赖于高度平台,并且会产生一些开销.
你必须在amd64上明确指定它而不是x386的原因只是它恰好是x86的默认值,而不是amd64.
另请注意,“-fpic”和“-fPIC”之间的区别：
-fpic
Generate position-independent code (PIC) suitable for use in a
shared library,if supported for the target machine. Such code
accesses all constant addresses through a global offset table
(GOT). The dynamic loader resolves the GOT entries when the pro-
gram starts (the dynamic loader is not part of GCC; it is part
of the operating system). If the GOT size for the linked execu-
table exceeds a machine-specific maximum size,you get an error
message from the linker indicating that -fpic does not work; in
that case,recompile with -fPIC instead. (These maximums are 8k
on the SPARC and 32k on the m68k and RS/6000. The 386 has no
such limit.)
Position-independent code requires special support,and there
fore works only on certain machines. For the 386,GCC supports
PIC for System V but not for the Sun 386i. Code generated for
the IBM RS/6000 is always position-independent.
When this flag is set,the macros __pic__ and __PIC__ are defined to 1.
-fPIC
If supported for the target machine,emit position-independent
code,suitable for dynamic linking and avoiding any limit on the
size of the global offset table. This option makes a difference
on the m68k,PowerPC and SPARC.
Position-independent code requires special support,and therefore
works only on certain machines.
When this flag is set,the macros __pic__ and __PIC__ are defined to 2.
