2012/3/12 Ludovic Courtès <ludovic.cour...@inria.fr>: > Hi, > > Ian Lance Taylor <i...@google.com> skribis: > >> ludovic.cour...@inria.fr (Ludovic Courtès) writes: >> >>> Ian Lance Taylor <i...@google.com> skribis: >>> >>>> ludovic.cour...@inria.fr (Ludovic Courtès) writes: >>>> >>>>> Ian Lance Taylor <i...@google.com> skribis: >>>>> >>>>>> ludovic.cour...@inria.fr (Ludovic Courtès) writes: >>>>>> >>>>>>> However, this means that plug-ins must now be built with g++, except >>>>>>> when GCC was configured with --disable-build-poststage1-with-cxx. This >>>>>>> seems difficult to deal with, for plug-in writers. >>>>>> >>>>>> This is an unfortunate truth during our transition to building gcc with >>>>>> C++. There is going to be a period of time when the compiler may be >>>>>> built as either C or C++. The end goal is for the compiler to always be >>>>>> built with C++, but until we reach that state I think plugin writers >>>>>> will have to test. >>>>> >>>>> What about wrapping the C API in extern "C"? >>>> >>>> We eventually will want the internal APIs to be C++, so this transition >>>> will inevitably happen at some point. >>> >>> I understand the goal. However, should a C++ API be added, the C-only >>> part could still be kept extern "C". >> >> We are talking here about internal GCC functions. We are not talking >> about an actual defined API. The defined API is in plugin-api.h, and >> that remains extern "C". There is no "C-only part" of the internal API. > > Hmm <plugin-api.h> is for linker plug-ins; <gcc-plugin.h> provides > nothing more than the event mechanism. > > Symbols declared in <tree.h> are mangled, for instance. I’m not sure > whether <tree.h> is considered internal or not, but I can hardly see > what kind of plug-in could be written without using it. > >>> For 4.7.0, as Duncan Sands writes, it would be a very helpful for the >>> ABI to be independent of configuration options–i.e., either mangled or >>> unmangled symbols. >> >> That just postpones the pain to gcc 4.8.0. > > In 4.8 things will be easier: plug-ins will have to be compiled with g++. > > In 4.7, finding out whether gcc or g++ should be used is left as an > exercise to the plug-in writer, which is inconvenient at best.
Well, that is what you get for having plugins without a proper plugin API ;) It's not going to change for 4.7. Anybody who is willing to attack the fundamental plugin issue is advised to develop a separate, stable (and thus forward-looking) C plugin interface (and make all other symbols hidden again). Richard. > Thanks, > Ludo’.
