iains added a comment. In D134267#3869614 <https://reviews.llvm.org/D134267#3869614>, @dblaikie wrote:
> In D134267#3869162 <https://reviews.llvm.org/D134267#3869162>, @iains wrote: > >> In D134267#3868830 <https://reviews.llvm.org/D134267#3868830>, @dblaikie >> wrote: >> >>> I'm OK with sticking with the existing `-fmodule-file` if that works for >>> everyone. Yeah, it's short and ambiguous in a space with many concepts of >>> what a "module file" is, but also the fact that it's a `-f` flag might help >>> disambiguate it a bit - it's probably not the way anyone would think/expect >>> to be passing source files, those just get passed without flags on the >>> command line. And any use of it will show the .pcm extension or whatever >>> that should make it clear enough what's going on. >> >> hmm (I realise I mentioned this, and hope it has not complicated things) .. >> >> .. I was thinking of the `-fmodule-file=<name>=filename` variant. The >> problem with using it without (the <name>) is that -fmodule-file= can (and >> does) appear multiple times on the command line to specify dependent modules >> - so that one would have to specify which (named) module was related to the >> filename. > I /think/ currently `-fmodule-file` works with Clang header modules > presumably because the module files contain within them enough information to > enable the compiler to substitute the module for an include where necessary? > I'm not sure the `<name>=` part is necessary, as such, if the BMIs can > reasonably contain enough identifying info to make their use clear to the > consumer. `-fmodule-file=` works with both `clang` modules and standard C++ ones. What it does (as of now) is cause the FE to open the named file and to pre-load the module name - so that when the FE tries to find a module the lookup mechanism can associate the module name with the module data. So, if we need 3 dependent modules to be available when building a new source .. we would specify the PCM files containing those modules. At present, if you try to specify a non-existent PCM using `-fmodule-file=` the compile will fail early on (it is expecting this to indicate a source module, not a destination one). However, the second syntax `-fmodule-file=<name>=filename` I think should be able to work around this (since it says that the named module <name> is associated with the PCM `filename` which would allow us to cater for that file being missing (when we are creating it). Does that clarify at all ? It would be great not to add more modules options flags, there are already way to many :/ - but if this seems too complex then one of the spellings suggested by @ChuanqiXu would work. CHANGES SINCE LAST ACTION https://reviews.llvm.org/D134267/new/ https://reviews.llvm.org/D134267 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
