Why constructor still be exported when I using -fvisibility=hidden

Question

I have a class A:

class A
{
public:
   A() {}
   virtual ~A() {}

   void Func();
};

and another class M using A. I want to create libM.so which hidden all A's symbols. I using the following script to compile it:

g++ -c A.cc -fPIC -fvisibility=hidden
g++ -c M.cc -fPIC
g++ -shared -z defs -o libM.so M.o A.o

But when I using "nm -DC libM.so", it still has

0000000000000c78 W A::A()
0000000000000c78 W A::A()

I search this question on google and found another gcc option: "-fvisibility-inlines-hidden" to hidden inline functions, but I still got the same result even add this option when compile A.o

g++ -c A.cc -fPIC -fvisibility=hidden -fvisibility-inlines-hidden

Why "-fvisibility-inlines-hidden" doesn't have effect? How do I prevent A::A() to appear in libM.so's export symbol? Thank you very much!

The inline constructor will be defined in both translation units, so presumably you need the compiler option for both, not just A.cc. (Not an answer since I don't have a computer available to test my guess at the moment) — Mike Seymour
Thank you very much! Yes, it is right. I should add -fvisibility-inlines-hidden when I compile M.cc. — cgspwei
Please answer your own question with what you've found out and accept it to close this issue. — vonbrand

cgspwei cgspwei · Accepted Answer · 2013-01-31T04:40:59

Thanks to Mike Seymour. I should add -fvisibility-inlines-hidden when I compile M.cc

g++ -c A.cc -fPIC -fvisibility=hidden -fvisibility-inlines-hidden
g++ -c M.cc -fPIC -fvisibility-inlines-hidden
g++ -shared -z defs -o libM.so M.o A.o

Why constructor still be exported when I using -fvisibility=hidden

1 Answers