===== Setup =====
I'm writing a library that I would like to be able to compile with multiple versions of gcc on multiple platforms. The library is used by a larger project, and we need portability. Using the latest gcc is not always an option, so we live with multiple versions. I can't change this.
My library contains STL.
To avoid code bloat, it uses explicit template instantiation.
===== The offending code =====
There is lots of offending code, but it is all similar. I have code that looks like this:
template map<string, void*, CaseIgnLTStr>; template map<string, void*, CaseIgnLTStr>::iterator;
This doesn't compile with gcc 3.4. Line #1 is no problem: I just have to add "class", like so:
template class map<string, void*, CaseIgnLTStr>;
The second line--the one with the iterator--is the real problem. It is needed or I get linking error. However, it is apparently no longer acceptable code because iterator is a typdef. The gcc 3.4 release notes state:
# Using a name introduced by a typedef in a friend declaration or in an explicit instantiation is now rejected, as specified by the ISO C++ standard.
(From http://gcc.gnu.org/gcc-3.4/changes.html#cplusplus )
====== The resolution? =====
I'm trying to figure out my options.
1) Give up and use implict template instantiation.
2) Unwind the typedefs and instantiate what I need. This is pain, it's ugly, and it may not be portable across versions of the compiler.
3) Rewrite my code to not use STL.
4) Whine loudly and see if I can get someone to listen.
#3 is probably a bad idea and #4 doesn't seem likely to help. I'm not terribly happy with #1 or #2, but I would listen to arguments for them. Is there anything else I can do?
Thanks, -alain
