Bug#490173: g++-4.3: Doesn't hide (visibility-wise) vtables and VTTs on ARM

[Mike Hommey <mh@glandium.org>]

Package: g++-4.3
Version: 4.3.1-4
Severity: important

This bug causes FTBFS of webkit on ARM:
http://buildd.debian.org/fetch.cgi?pkg=webkit;ver=1.0.1-1;arch=armel;stamp=1215557168

The problem can be seen on the following code:
-----8<---------
class A {
public:
  int a;
  virtual int v();
};

int A::v() {
  return 2;
}

class B : public A {
public:
  int b;
};

extern "C" __attribute__((visibility("default"))) int test(void) {
  B *b = new B;
  return b->v();
}
-------->8-------

Build with: g++ -fvisibility=hidden -o test.o -c test.cpp
Take a look at symbols with objdump -x test.o

Relevant part:
00000000 g     O .rodata        0000000c _ZTV1A
00000000  w    O .rodata._ZTV1B 0000000c _ZTV1B

These should be marked .hidden.

Resulting shared library (g++ -shared -fvisibility=hidden -o test.so test.cpp)
exports both _ZTV1A and _ZTV1B symbols as a result of this, which is
unexpected.

Proper result is obtained on other architectures (x86 below):
00000000  w    O .rodata._ZTV1A 0000000c .hidden _ZTV1A
00000000  w    O .rodata._ZTV1B 0000000c .hidden _ZTV1B

Note this may be related to the fact that apparently, ARM doesn't have vtables
in .rodata.

Mike

-- System Information:
Debian Release: 4.0
  APT prefers proposed-updates
  APT policy: (500, 'proposed-updates'), (500, 'stable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.18-6-686
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)