[clang] [clang][deps] Add module map describing compiled module to file dependencies. (PR #160226)

[Jan Svoboda via cfe-commits]

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@@ -685,6 +685,13 @@ void ModuleDepCollectorPP::EndOfMainFile() {
   if (!MDC.ScanInstance.getPreprocessorOpts().ImplicitPCHInclude.empty())
     MDC.addFileDep(MDC.ScanInstance.getPreprocessorOpts().ImplicitPCHInclude);
 
+  if (Module *CurrentModule = PP.getCurrentModuleImplementation()) {
+    if (OptionalFileEntryRef CurrentModuleMap =
+            PP.getHeaderSearchInfo().getModuleMap().getModuleMapFileForUniquing(
+                CurrentModule))
+      MDC.addFileDep(CurrentModuleMap->getName());
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jansvoboda11 wrote:

The failure is expected. The `"file-deps"` field is intended for consumption by tools that might not understand Clang's virtual filesystem overlays, so the only thing they can reason about is the on-disk path for files (`"external-contents"` in the VFS overlay file). That's of course different from what we put on the command-line for Clang itself, as Ben explained above.

https://github.com/llvm/llvm-project/pull/160226