在使用 g++ 创建的共享库中隐藏实例化模板
我有一个包含以下内容的文件:
#include <map>A类{}；无效 doSomething() {std::map<int, A>米；}当使用 g++ 编译成共享库时，该库包含 std::map 的所有方法的动态符号.由于 A 对该文件是私有的，因此 std::map 不可能在具有相同参数的任何其他共享库中实例化，所以我想隐藏模板实例化(出于本文档中描述的一些原因).p>
我认为我应该能够通过添加模板类的显式实例并将其标记为隐藏来做到这一点，如下所示:
#include <map>A类{}；模板类 __attribute__((visibility ("hidden"))) std::map;无效 doSomething() {std::map<int, A>米；} 但是，这没有任何效果:符号仍然全部导出.我还尝试使用以下命令包围整个文件:
#pragma GCC可见性推送(隐藏)...#pragma GCC 可见性弹出但这对 std::map<int, A> 方法的可见性也没有影响(尽管它确实隐藏了 doSomething).同样，使用 -fvisibility=hidden 编译对 std::map 的方法的可见性没有影响.
我上面链接的文档描述了使用导出地图来限制可见性，但这似乎很乏味.
有没有办法在 g++ 中做我想做的事情(除了使用导出映射)?如果是这样，它是什么?如果没有，是否有充分的理由为什么必须始终导出这些符号，或者这只是 g++ 中的一个遗漏?
解决方案来自 GCC 错误报告 #36022，标记为 INVALID，Benjamin Kosnik 评论道:
<块引用>[A]n 将在 DSO 之间抛出的异常类必须是用默认可见性显式标记，以便 `type_info' 节点将DSO 之间的统一.因此，libstdc++ 具有命名空间 std 的基本原理具有可见性默认."
另外，查看 std::map 的 libstdc++ 源代码(我的在 /usr/include/c++/4.4.4/bits/stl_map.h 中)，看来 libstdc++ 强制默认可见性的方式是使用 _GLIBCXX_BEGIN_NESTED_NAMESPACE 宏，该宏在 stl_map.h 的顶部使用:
#define _GLIBCXX_VISIBILITY_ATTR(V) __attribute__ ((__visibility__ (#V)))# 定义 _GLIBCXX_BEGIN_NESTED_NAMESPACE(X, Y) _GLIBCXX_BEGIN_NAMESPACE(X)# 定义 _GLIBCXX_BEGIN_NAMESPACE(X) 命名空间 X _GLIBCXX_VISIBILITY_ATTR(default) {因此，您的 STL 实现明确覆盖 -fvisibility=hidden 和 #pragma GCC visibility push(hidden)/#pragma GCC visibility pop.
如果你真的想强制 std::map 成员隐藏可见性，那么我认为你可以使用类似的东西:
//确保默认可见性与任何用作异常类型的类一起使用#include <内存>#include <新>#include <stdexcept>//现在使用隐藏可见性包含 `std::map` 的定义#include <bits/c++config.h>#undef _GLIBCXX_VISIBILITY_ATTR#define _GLIBCXX_VISIBILITY_ATTR(V) __attribute__ ((__visibility__ ("hidden")))#include <地图>#undef _GLIBCXX_VISIBILITY_ATTR#define _GLIBCXX_VISIBILITY_ATTR(V) __attribute__ ((__visibility__ (#V)))//恢复`_GLIBCXX_VISIBILITY_ATTR`然后，以下一系列命令将验证 std::map 成员是否可以从共享对象中剥离:
g++ -c -fPIC -fvisibility=hidden test.cppg++ -shared -Wl,-soname,libtest.so.1 -o libtest.so.1.0 test.ostrip -x libtest.so.1.0readelf -s libtest.so.1.0
请注意，在第 3 步之前，readelf -s libtest.so.1.0 打印(对我而言):
符号表 '.dynsym' 包含 23 个条目:Num:值大小类型绑定 Vis Ndx 名称0: 00000000 0 NOTYPE 本地默认值1: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__2:00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses3: 00000000 0 FUNC 全局默认值 UND _ZdlPv@GLIBCXX_3.4 (2)4:00000000 0 FUNC 全局默认值和 __gxx_personality_v0@CXXABI_1.3 (3)5:00000000 0 FUNC 全局默认值 UND _Unwind_Resume@GCC_3.0 (4)6: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@GLIBC_2.1.3 (5)7: 00000d02 5 功能弱默认 12 _ZNSt4pairIKi1AED1Ev8: 00000d6c 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEEC1ISt9: 00000d96 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca10: 000023bc 0 NOTYPE 全球默认 ABS _end11: 000023b4 0 NOTYPE 全球默认 ABS _edata12:00000d5e 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca13: 000023b4 0 NOTYPE 全球默认 ABS __bss_start14: 00000bac 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca15:00000d08 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca16:000007f4 0 FUNC 全局默认值 10 _init17: 00000c4a 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS18:00000df8 0 FUNC 全局默认值 13 _fini19:00000dba 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca20: 00000cde 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEED1Ev21: 00000d90 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca22: 00000ac6 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS符号表 '.symtab' 包含 84 个条目:Num:值大小类型绑定 Vis Ndx 名称0: 00000000 0 NOTYPE 本地默认值1: 000000f4 0 部分本地默认值 12: 00000118 0 部分本地默认值 23: 000001c0 0 部分本地默认值 34: 0000022c 0 部分本地默认值 45: 0000039c 0 部分本地默认值 56: 000006b6 0 部分本地默认值 67: 000006e4 0 部分本地默认值 78: 00000754 0 部分本地默认值 89: 0000077c 0 部分本地默认值 910: 000007f4 0 部分本地默认值 1011: 00000824 0 部分本地默认值 1112: 00000930 0 部分本地默认值 1213: 00000df8 0 部分本地默认值 1314: 00000e14 0 部分本地默认值 1415: 00000ef8 0 部分本地默认值 1516: 00001240 0 部分本地默认值 1617: 0000225c 0 部分本地默认值 1718: 00002264 0 部分本地默认值 1819: 0000226c 0 部分本地默认值 1920: 00002270 0 部分本地默认值 2021: 00002358 0 部分本地默认值 2122: 00002364 0 部分本地默认值 2223: 000023ac 0 部分本地默认值 2324: 000023b4 0 部分本地默认值 2425: 00000000 0 部分本地默认值 2526: 00000000 0 文件本地默认 ABS crtstuff.c27: 0000225c 0 对象本地默认值 17 __CTOR_LIST__28:00002264 0 对象本地默认值 18 __DTOR_LIST__29: 0000226c 0 对象本地默认值 19 __JCR_LIST__30:00000930 0 FUNC 本地默认值 12 __do_global_dtors_aux31: 000023b4 1 对象本地默认值 24 已完成.594232:000023b8 4 对象本地默认值 24 dtor_idx.594433: 000009b0 0 FUNC 本地默认值 12 frame_dummy34: 00000000 0 文件本地默认 ABS crtstuff.c35:00002260 0 对象本地默认值 17 __CTOR_END__36: 0000123c 0 对象本地默认值 15 __FRAME_END__37:0000226c 0 对象本地默认值 19 __JCR_END__38: 00000dc0 0 FUNC 本地默认值 12 __do_global_ctors_aux39: 00000000 0 文件本地默认 ABS 测试.cpp40: 00000d64 8 FUNC 本地隐藏 12 _ZNKSt8_Rb_treeIiSt4pairI41: 000023b0 4 对象本地隐藏 23 DW.ref.__gxx_personality_42: 00000b40 11 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK43: 00000bc8 129 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK44: 00000bb1 11 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK45: 00000b4c 96 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK46: 00000ca0 62 FUNC 本地隐藏 12 _ZNKSt8_Rb_treeIiSt4pairI47: 00000ab2 19 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK48: 00002364 0 对象本地隐藏 ABS _GLOBAL_OFFSET_TABLE_49:00000a56 92 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK50: 000009ec 30 FUNC 本地隐藏 12 _Z11doSomethingv51: 00000c6e 49 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK52:00000a32 35 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK53: 000023ac 0 对象本地隐藏 23 __dso_handle54: 00000a0a 19 FUNC 本地隐藏 12 _ZNSt3mapIi1ASt4lessIiESa55:00002268 0 对象本地隐藏 18 __DTOR_END__56: 00000bbc 11 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK57: 00000a1e 19 FUNC 本地隐藏 12 _ZNSt3mapIi1ASt4lessIiESa58: 00000d2c 50 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK59: 00000aea 85 FUNC 本地隐藏 12 _ZNSt8_Rb_treeIiSt4pairIK60: 000009e7 0 FUNC 本地隐藏 12 __i686.get_pc_thunk.bx61: 00002270 0 对象本地隐藏 ABS _DYNAMIC62: 00000d02 5 功能弱默认 12 _ZNSt4pairIKi1AED1Ev63: 00000c4a 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS64: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__65:00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses66:00000000 0 FUNC 全局默认值 UND _ZdlPv@@GLIBCXX_3.467:00000df8 0 FUNC 全局默认值 13 _fini68: 00000d6c 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEEC1ISt69:00000dba 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca70: 00000cde 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEED1Ev71: 00000d5e 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca72: 00000d90 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca73: 000023b4 0 NOTYPE 全球默认 ABS __bss_start74: 00000d96 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca75: 00000bac 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca76: 000023bc 0 NOTYPE 全球默认 ABS _end77: 000023b4 0 NOTYPE 全球默认 ABS _edata78: 00000ac6 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS79: 00000000 0 FUNC 全局默认值和 __gxx_personality_v0@@CXX80: 00000000 0 FUNC 全局默认值 UND _Unwind_Resume@@GCC_3.081: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@@GLIBC_2.182:00000d08 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca83: 000007f4 0 FUNC 全局默认值 10 _init然后:
符号表 '.dynsym' 包含 23 个条目:Num:值大小类型绑定 Vis Ndx 名称0: 00000000 0 NOTYPE 本地默认值1: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__2:00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses3: 00000000 0 FUNC 全局默认值 UND _ZdlPv@GLIBCXX_3.4 (2)4:00000000 0 FUNC 全局默认值和 __gxx_personality_v0@CXXABI_1.3 (3)5:00000000 0 FUNC 全局默认值 UND _Unwind_Resume@GCC_3.0 (4)6: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@GLIBC_2.1.3 (5)7: 00000d02 5 功能弱默认 12 _ZNSt4pairIKi1AED1Ev8: 00000d6c 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEEC1ISt9: 00000d96 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca10: 000023bc 0 NOTYPE 全球默认 ABS _end11: 000023b4 0 NOTYPE 全球默认 ABS _edata12:00000d5e 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca13: 000023b4 0 NOTYPE 全球默认 ABS __bss_start14: 00000bac 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca15:00000d08 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca16:000007f4 0 FUNC 全局默认值 10 _init17: 00000c4a 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS18:00000df8 0 FUNC 全局默认值 13 _fini19:00000dba 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca20: 00000cde 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEED1Ev21: 00000d90 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca22: 00000ac6 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS符号表 '.symtab' 包含 51 个条目:Num:值大小类型绑定 Vis Ndx 名称0: 00000000 0 NOTYPE 本地默认值1: 000000f4 0 部分本地默认值 12: 00000118 0 部分本地默认值 23: 000001c0 0 部分本地默认值 34: 0000022c 0 部分本地默认值 45: 0000039c 0 部分本地默认值 56: 000006b6 0 部分本地默认值 67: 000006e4 0 部分本地默认值 78: 00000754 0 部分本地默认值 89: 0000077c 0 部分本地默认值 910: 000007f4 0 部分本地默认值 1011: 00000824 0 部分本地默认值 1112: 00000930 0 部分本地默认值 1213: 00000df8 0 部分本地默认值 1314: 00000e14 0 部分本地默认值 1415: 00000ef8 0 部分本地默认值 1516: 00001240 0 部分本地默认值 1617: 0000225c 0 部分本地默认值 1718: 00002264 0 部分本地默认值 1819: 0000226c 0 部分本地默认值 1920: 00002270 0 部分本地默认值 2021: 00002358 0 部分本地默认值 2122: 00002364 0 部分本地默认值 2223: 000023ac 0 部分本地默认值 2324: 000023b4 0 部分本地默认值 2425: 00000000 0 部分本地默认值 2526: 00000000 0 文件本地默认 ABS crtstuff.c27: 00000000 0 文件本地默认 ABS crtstuff.c28: 00000000 0 文件本地默认 ABS 测试.cpp29: 00000d02 5 功能弱默认 12 _ZNSt4pairIKi1AED1Ev30: 00000c4a 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS31: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__32:00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses33: 00000000 0 FUNC 全局默认值 UND _ZdlPv@@GLIBCXX_3.434:00000df8 0 FUNC 全局默认值 13 _fini35: 00000d6c 35 FUNC 弱默认值 12 _ZNSaISt4pairIKi1AEEC1ISt36:00000dba 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca37: 00000cde 35 功能弱默认 12 _ZNSaISt4pairIKi1AEED1Ev38: 00000d5e 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca39:00000d90 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca40: 000023b4 0 NOTYPE 全球默认 ABS __bss_start41: 00000d96 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca42: 00000bac 5 功能弱默认 12 _ZN9__gnu_cxx13new_alloca43: 000023bc 0 NOTYPE 全球默认 ABS _end44: 000023b4 0 NOTYPE 全球默认 ABS _edata45: 00000ac6 35 功能弱默认 12 _ZNSaISt13_Rb_tree_nodeIS46: 00000000 0 FUNC 全局默认值 UND __gxx_personality_v0@@CXX47:00000000 0 FUNC 全局默认值 UND _Unwind_Resume@@GCC_3.048: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@@GLIBC_2.149: 00000d08 35 功能弱默认 12 _ZN9__gnu_cxx13new_alloca50: 000007f4 0 FUNC 全局默认值 10 _init另见:
- 可见性 - GCC 维基
- 控制符号可见性
I have a file that contains the following:
#include <map>
class A {};
void doSomething() {
std::map<int, A> m;
}
When compiled into a shared library with g++, the library contains dynamic symbols for all the methods of std::map<int, A>. Since A is private to this file, there is no possibility that std::map will be instantiated in any other shared library with the same parameters, so I'd like to make the template instantiation hidden (for some of the reasons described in this document).
I thought I should be able to do this by adding an explicit instantiation of the template class and marking it as hidden, like so:
#include <map>
class A {};
template class __attribute__((visibility ("hidden"))) std::map<int, A>;
void doSomething() {
std::map<int, A> m;
}
However, this has no effect: the symbols are still all exported. I also tried surrounding the entire file with:
#pragma GCC visibility push(hidden)
...
#pragma GCC visibility pop
but this also has no effect on the visibility of the methods of std::map<int, A> (although it does hide doSomething). Similarly, compiling with -fvisibility=hidden has no effect on the visibility of the methods of std::map<int, A>.
The document I linked to above describes the use of export maps to restrict visibility, but that seems very tedious.
Is there a way to do what I want in g++ (other than using export maps)? If so, what is it? If not, is there a good reason why these symbols must always be exported, or is this just a omission in g++?
解决方案From GCC bug report #36022, which was marked INVALID, Benjamin Kosnik remarked:
[A]n exception class that will be thrown between DSOs must be explicitly marked with default visibility so that the `type_info' nodes will be unified between the DSOs. Thus, the rationale for libstdc++ having namespace std have visibility "default."
Also, looking through the libstdc++ source for std::map (mine is in /usr/include/c++/4.4.4/bits/stl_map.h), it appears that the way libstdc++ enforces default visibility is with the _GLIBCXX_BEGIN_NESTED_NAMESPACE macro that is used at the top of stl_map.h:
# define _GLIBCXX_VISIBILITY_ATTR(V) __attribute__ ((__visibility__ (#V)))
# define _GLIBCXX_BEGIN_NESTED_NAMESPACE(X, Y) _GLIBCXX_BEGIN_NAMESPACE(X)
# define _GLIBCXX_BEGIN_NAMESPACE(X) namespace X _GLIBCXX_VISIBILITY_ATTR(default) {
Therefore your STL implementation is explicitly overriding -fvisibility=hidden and #pragma GCC visibility push(hidden)/#pragma GCC visibility pop.
If you really wanted to force the std::map members to have hidden visibility then I think you could use something like:
// ensure that default visibility is used with any class that is used as an exception type
#include <memory>
#include <new>
#include <stdexcept>
// now include the definition of `std::map` using hidden visibility
#include <bits/c++config.h>
#undef _GLIBCXX_VISIBILITY_ATTR
#define _GLIBCXX_VISIBILITY_ATTR(V) __attribute__ ((__visibility__ ("hidden")))
#include <map>
#undef _GLIBCXX_VISIBILITY_ATTR
#define _GLIBCXX_VISIBILITY_ATTR(V) __attribute__ ((__visibility__ (#V))) // restore `_GLIBCXX_VISIBILITY_ATTR`
Then, the following series of commands will verify that the std::map<int, A> members can be stripped from a shared object:
g++ -c -fPIC -fvisibility=hidden test.cppg++ -shared -Wl,-soname,libtest.so.1 -o libtest.so.1.0 test.ostrip -x libtest.so.1.0readelf -s libtest.so.1.0
Note that before step 3, readelf -s libtest.so.1.0 printed (for me):
Symbol table '.dynsym' contains 23 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 00000000 0 NOTYPE LOCAL DEFAULT UND
1: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
2: 00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses
3: 00000000 0 FUNC GLOBAL DEFAULT UND _ZdlPv@GLIBCXX_3.4 (2)
4: 00000000 0 FUNC GLOBAL DEFAULT UND __gxx_personality_v0@CXXABI_1.3 (3)
5: 00000000 0 FUNC GLOBAL DEFAULT UND _Unwind_Resume@GCC_3.0 (4)
6: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@GLIBC_2.1.3 (5)
7: 00000d02 5 FUNC WEAK DEFAULT 12 _ZNSt4pairIKi1AED1Ev
8: 00000d6c 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEEC1ISt
9: 00000d96 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
10: 000023bc 0 NOTYPE GLOBAL DEFAULT ABS _end
11: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS _edata
12: 00000d5e 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
13: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS __bss_start
14: 00000bac 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
15: 00000d08 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
16: 000007f4 0 FUNC GLOBAL DEFAULT 10 _init
17: 00000c4a 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
18: 00000df8 0 FUNC GLOBAL DEFAULT 13 _fini
19: 00000dba 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
20: 00000cde 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEED1Ev
21: 00000d90 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
22: 00000ac6 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
Symbol table '.symtab' contains 84 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 00000000 0 NOTYPE LOCAL DEFAULT UND
1: 000000f4 0 SECTION LOCAL DEFAULT 1
2: 00000118 0 SECTION LOCAL DEFAULT 2
3: 000001c0 0 SECTION LOCAL DEFAULT 3
4: 0000022c 0 SECTION LOCAL DEFAULT 4
5: 0000039c 0 SECTION LOCAL DEFAULT 5
6: 000006b6 0 SECTION LOCAL DEFAULT 6
7: 000006e4 0 SECTION LOCAL DEFAULT 7
8: 00000754 0 SECTION LOCAL DEFAULT 8
9: 0000077c 0 SECTION LOCAL DEFAULT 9
10: 000007f4 0 SECTION LOCAL DEFAULT 10
11: 00000824 0 SECTION LOCAL DEFAULT 11
12: 00000930 0 SECTION LOCAL DEFAULT 12
13: 00000df8 0 SECTION LOCAL DEFAULT 13
14: 00000e14 0 SECTION LOCAL DEFAULT 14
15: 00000ef8 0 SECTION LOCAL DEFAULT 15
16: 00001240 0 SECTION LOCAL DEFAULT 16
17: 0000225c 0 SECTION LOCAL DEFAULT 17
18: 00002264 0 SECTION LOCAL DEFAULT 18
19: 0000226c 0 SECTION LOCAL DEFAULT 19
20: 00002270 0 SECTION LOCAL DEFAULT 20
21: 00002358 0 SECTION LOCAL DEFAULT 21
22: 00002364 0 SECTION LOCAL DEFAULT 22
23: 000023ac 0 SECTION LOCAL DEFAULT 23
24: 000023b4 0 SECTION LOCAL DEFAULT 24
25: 00000000 0 SECTION LOCAL DEFAULT 25
26: 00000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
27: 0000225c 0 OBJECT LOCAL DEFAULT 17 __CTOR_LIST__
28: 00002264 0 OBJECT LOCAL DEFAULT 18 __DTOR_LIST__
29: 0000226c 0 OBJECT LOCAL DEFAULT 19 __JCR_LIST__
30: 00000930 0 FUNC LOCAL DEFAULT 12 __do_global_dtors_aux
31: 000023b4 1 OBJECT LOCAL DEFAULT 24 completed.5942
32: 000023b8 4 OBJECT LOCAL DEFAULT 24 dtor_idx.5944
33: 000009b0 0 FUNC LOCAL DEFAULT 12 frame_dummy
34: 00000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
35: 00002260 0 OBJECT LOCAL DEFAULT 17 __CTOR_END__
36: 0000123c 0 OBJECT LOCAL DEFAULT 15 __FRAME_END__
37: 0000226c 0 OBJECT LOCAL DEFAULT 19 __JCR_END__
38: 00000dc0 0 FUNC LOCAL DEFAULT 12 __do_global_ctors_aux
39: 00000000 0 FILE LOCAL DEFAULT ABS test.cpp
40: 00000d64 8 FUNC LOCAL HIDDEN 12 _ZNKSt8_Rb_treeIiSt4pairI
41: 000023b0 4 OBJECT LOCAL HIDDEN 23 DW.ref.__gxx_personality_
42: 00000b40 11 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
43: 00000bc8 129 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
44: 00000bb1 11 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
45: 00000b4c 96 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
46: 00000ca0 62 FUNC LOCAL HIDDEN 12 _ZNKSt8_Rb_treeIiSt4pairI
47: 00000ab2 19 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
48: 00002364 0 OBJECT LOCAL HIDDEN ABS _GLOBAL_OFFSET_TABLE_
49: 00000a56 92 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
50: 000009ec 30 FUNC LOCAL HIDDEN 12 _Z11doSomethingv
51: 00000c6e 49 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
52: 00000a32 35 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
53: 000023ac 0 OBJECT LOCAL HIDDEN 23 __dso_handle
54: 00000a0a 19 FUNC LOCAL HIDDEN 12 _ZNSt3mapIi1ASt4lessIiESa
55: 00002268 0 OBJECT LOCAL HIDDEN 18 __DTOR_END__
56: 00000bbc 11 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
57: 00000a1e 19 FUNC LOCAL HIDDEN 12 _ZNSt3mapIi1ASt4lessIiESa
58: 00000d2c 50 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
59: 00000aea 85 FUNC LOCAL HIDDEN 12 _ZNSt8_Rb_treeIiSt4pairIK
60: 000009e7 0 FUNC LOCAL HIDDEN 12 __i686.get_pc_thunk.bx
61: 00002270 0 OBJECT LOCAL HIDDEN ABS _DYNAMIC
62: 00000d02 5 FUNC WEAK DEFAULT 12 _ZNSt4pairIKi1AED1Ev
63: 00000c4a 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
64: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
65: 00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses
66: 00000000 0 FUNC GLOBAL DEFAULT UND _ZdlPv@@GLIBCXX_3.4
67: 00000df8 0 FUNC GLOBAL DEFAULT 13 _fini
68: 00000d6c 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEEC1ISt
69: 00000dba 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
70: 00000cde 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEED1Ev
71: 00000d5e 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
72: 00000d90 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
73: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS __bss_start
74: 00000d96 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
75: 00000bac 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
76: 000023bc 0 NOTYPE GLOBAL DEFAULT ABS _end
77: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS _edata
78: 00000ac6 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
79: 00000000 0 FUNC GLOBAL DEFAULT UND __gxx_personality_v0@@CXX
80: 00000000 0 FUNC GLOBAL DEFAULT UND _Unwind_Resume@@GCC_3.0
81: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@@GLIBC_2.1
82: 00000d08 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
83: 000007f4 0 FUNC GLOBAL DEFAULT 10 _init
And afterward:
Symbol table '.dynsym' contains 23 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 00000000 0 NOTYPE LOCAL DEFAULT UND
1: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
2: 00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses
3: 00000000 0 FUNC GLOBAL DEFAULT UND _ZdlPv@GLIBCXX_3.4 (2)
4: 00000000 0 FUNC GLOBAL DEFAULT UND __gxx_personality_v0@CXXABI_1.3 (3)
5: 00000000 0 FUNC GLOBAL DEFAULT UND _Unwind_Resume@GCC_3.0 (4)
6: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@GLIBC_2.1.3 (5)
7: 00000d02 5 FUNC WEAK DEFAULT 12 _ZNSt4pairIKi1AED1Ev
8: 00000d6c 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEEC1ISt
9: 00000d96 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
10: 000023bc 0 NOTYPE GLOBAL DEFAULT ABS _end
11: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS _edata
12: 00000d5e 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
13: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS __bss_start
14: 00000bac 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
15: 00000d08 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
16: 000007f4 0 FUNC GLOBAL DEFAULT 10 _init
17: 00000c4a 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
18: 00000df8 0 FUNC GLOBAL DEFAULT 13 _fini
19: 00000dba 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
20: 00000cde 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEED1Ev
21: 00000d90 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
22: 00000ac6 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
Symbol table '.symtab' contains 51 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 00000000 0 NOTYPE LOCAL DEFAULT UND
1: 000000f4 0 SECTION LOCAL DEFAULT 1
2: 00000118 0 SECTION LOCAL DEFAULT 2
3: 000001c0 0 SECTION LOCAL DEFAULT 3
4: 0000022c 0 SECTION LOCAL DEFAULT 4
5: 0000039c 0 SECTION LOCAL DEFAULT 5
6: 000006b6 0 SECTION LOCAL DEFAULT 6
7: 000006e4 0 SECTION LOCAL DEFAULT 7
8: 00000754 0 SECTION LOCAL DEFAULT 8
9: 0000077c 0 SECTION LOCAL DEFAULT 9
10: 000007f4 0 SECTION LOCAL DEFAULT 10
11: 00000824 0 SECTION LOCAL DEFAULT 11
12: 00000930 0 SECTION LOCAL DEFAULT 12
13: 00000df8 0 SECTION LOCAL DEFAULT 13
14: 00000e14 0 SECTION LOCAL DEFAULT 14
15: 00000ef8 0 SECTION LOCAL DEFAULT 15
16: 00001240 0 SECTION LOCAL DEFAULT 16
17: 0000225c 0 SECTION LOCAL DEFAULT 17
18: 00002264 0 SECTION LOCAL DEFAULT 18
19: 0000226c 0 SECTION LOCAL DEFAULT 19
20: 00002270 0 SECTION LOCAL DEFAULT 20
21: 00002358 0 SECTION LOCAL DEFAULT 21
22: 00002364 0 SECTION LOCAL DEFAULT 22
23: 000023ac 0 SECTION LOCAL DEFAULT 23
24: 000023b4 0 SECTION LOCAL DEFAULT 24
25: 00000000 0 SECTION LOCAL DEFAULT 25
26: 00000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
27: 00000000 0 FILE LOCAL DEFAULT ABS crtstuff.c
28: 00000000 0 FILE LOCAL DEFAULT ABS test.cpp
29: 00000d02 5 FUNC WEAK DEFAULT 12 _ZNSt4pairIKi1AED1Ev
30: 00000c4a 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
31: 00000000 0 NOTYPE WEAK DEFAULT UND __gmon_start__
32: 00000000 0 NOTYPE WEAK DEFAULT UND _Jv_RegisterClasses
33: 00000000 0 FUNC GLOBAL DEFAULT UND _ZdlPv@@GLIBCXX_3.4
34: 00000df8 0 FUNC GLOBAL DEFAULT 13 _fini
35: 00000d6c 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEEC1ISt
36: 00000dba 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
37: 00000cde 35 FUNC WEAK DEFAULT 12 _ZNSaISt4pairIKi1AEED1Ev
38: 00000d5e 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
39: 00000d90 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
40: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS __bss_start
41: 00000d96 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
42: 00000bac 5 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
43: 000023bc 0 NOTYPE GLOBAL DEFAULT ABS _end
44: 000023b4 0 NOTYPE GLOBAL DEFAULT ABS _edata
45: 00000ac6 35 FUNC WEAK DEFAULT 12 _ZNSaISt13_Rb_tree_nodeIS
46: 00000000 0 FUNC GLOBAL DEFAULT UND __gxx_personality_v0@@CXX
47: 00000000 0 FUNC GLOBAL DEFAULT UND _Unwind_Resume@@GCC_3.0
48: 00000000 0 FUNC WEAK DEFAULT UND __cxa_finalize@@GLIBC_2.1
49: 00000d08 35 FUNC WEAK DEFAULT 12 _ZN9__gnu_cxx13new_alloca
50: 000007f4 0 FUNC GLOBAL DEFAULT 10 _init
See also:
- Visibility - GCC Wiki
- Controlling Symbol Visibility
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