[modules] Add -cc1 flag -fmodules-embed-all-files.

This flag causes all files that were read by the compilation to be embedded
into a produced module file. This is useful for distributed build systems that
use an include scanning system to determine which files are "needed" by a
compilation, and only provide those files to remote compilation workers. Since
using a module can require any file that is part of that module (or anything it
transitively includes), files that are not found by an include scanner can be
required in a regular build using explicit modules. With this flag, only files
that are actually referenced by transitively-#included files are required to be
present on the build machine.

llvm-svn: 253950

1 files changed, 3 insertions, 0 deletions

diff --git a/clang/include/clang/Driver/CC1Options.td b/clang/include/clang/Driver/CC1Options.td
index 56caea85b17..d510e19ea91 100644
--- a/clang/include/clang/Driver/CC1Options.td
+++ b/clang/include/clang/Driver/CC1Options.td
@@ -381,6 +381,9 @@ def fmodules_embed_file_EQ : Joined<["-"], "fmodules-embed-file=">,
   MetaVarName<"<file>">,
   HelpText<"Embed the contents of the specified file into the module file "
            "being compiled.">;
+def fmodules_embed_all_files : Joined<["-"], "fmodules-embed-all-files">,
+  HelpText<"Embed the contents of all files read by this compilation into "
+           "the produced module file.">;
 def fmodules_local_submodule_visibility :
   Flag<["-"], "fmodules-local-submodule-visibility">,
   HelpText<"Enforce name visibility rules across submodules of the same "