c++ - Compilation error Friend class unable to access field -

i trying compile qt5.3
files in question qv4executableallocator_p.h , qv4executableallocator.cpp. relevant code snippet header below

 struct allocation{     allocation()     : addr(0)     , size(0)     , free(true)     , next(0)     , prev(0)     {}     void *start() const;     void invalidate() { addr = 0; }     bool isvalid() const { return addr != 0; }     void deallocate(executableallocator *allocator);     private:         ~allocation() {}         friend class executableallocator;         allocation *split(size_t dividingsize);         bool mergenext(executableallocator *allocator);         bool mergeprevious(executableallocator *allocator);         quintptr addr;         uint size : 31; // more 2gb of function code? nah :)         uint free : 1;         allocation *next;         allocation *prev; };   

in cpp function executableallocator::chunkofpages::~chunkofpages() compilation error when trying access alloc->next.

qv4::executableallocator::allocation* qv4::executableallocator::allocation::next’ private 

code can seen online @ https://qt.gitorious.org/qt/qtdeclarative/source/be6c91acc3ee5ebb8336b9e79df195662ac11788:src/qml/jsruntime

my gcc version relatively old... 4.1
issue or else wrong in environment. way go forward. stuck compiler, since 1 have use on target platform

i'd guess qv4::executableallocator::chunkofpages struct not directly befriended allocation, can't access allocation's private data in destructor in c++ prior c++11 standard.

try adding friend struct executableallocator::chunkofpages allocation definition, should trick.

there slight change in way nested classes handled in c++11 (cited cppreference.com):

prior c++11, member declarations , definitions inside nested class of friend of class t cannot access private , protected members of class t, compilers accept in pre-c++11 mode.

which explain why worked in new compiler, not in old one.