I admit that I'm partly fishing here, but my proposal is based on the following:
* The implementation of PCH in GCC is atrocious and hard to maintain. * The next C++ standard is likely to define modules (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3347.pdf) * The user-base for PCH is negligibly small (here's where I'm mostly guessing). * PCH is absolutely useless for C. Removing PCH will give us more implementation freedom for the memory management project (http://gcc.gnu.org/wiki/cxx-conversion/gc-alternatives). With some effort, we could revive the streaming work done in the PPH branch and re-implement PCH with it (when we abandoned the branch, we were probably 80% complete as a PCH replacement). If we could at least remove support for C, then I can see a streaming-based PCH for the 4.9 release. Thoughts? Are there any big PCH users out there? Thanks. Diego.
