[cfe-dev] Language not recognized: 'c++-module-cpp-output'

[Boris Kolpackov via cfe-dev]

David Blaikie <dblaikie at gmail.com> writes:

> As an aside - Clang has -frewrite-includes that might be sufficiently
> similar for your needs. If you don't use this (& use full preprocessing)
> you will find that Clang's diagnostics differ between a preprocessed file
> being compiled and an unpreprocessed file being compiled (Clang uses macro
> information to decide whether to warn in some cases).

Yes, I use -frewrite-includes to partially preprocess before compiling.

The difference between -frewrite-includes and GCC's -fdirectives-only
is that for the latter you pass this option both when preprocessing (to
indicate that only partial preprocessing is required) and when compiling
(to indicate that the source is already partially preprocessed).

Boris