ChuanqiXu added a comment. In D121098#3383835 <https://reviews.llvm.org/D121098#3383835>, @iains wrote:
>> I am a little bit confused for the intuition. Couldn't we just import the >> pre-processed header? What's the problem? Could you elaborate on this? > > We cannot import a pre-processed file; the preprocessed file is still source > code, not a CMI. But if I understand correctly, we are able to import a pre-processed file as a header unit. Couldn't we? For example: // cc -E foo.h > foo.preprocessed import "foo.preprocessed" ... Is this not acceptable? > In addition, the pre-processor output for a header unit requires further > pre-processing on read. > This is because a header unit actually preserves some of the pre-processor > information [macro definitions] (which would normally be discarded after > phase 4). > > Header units are identifiable by a name (in common with GCC, we make the name > == the path by which the header is specified) -- that name is intentionally > not a legal named module name (neither is it, in general, a legal > identifier). So it doesn't eliminate my confusion. I guess there is some workflows that we need to import a preprocessed header as header unit (and we need to find the position of original file). Or in what circumstances, do we need to import a pre-processed header as header unit? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D121098/new/ https://reviews.llvm.org/D121098 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
