[clang] [clang][deps] Load module map file from PCM (PR #66389)

[Jan Svoboda via cfe-commits]

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@@ -1307,6 +1307,9 @@ void ModuleMap::setInferredModuleAllowedBy(Module *M,
 
 std::error_code
 ModuleMap::canonicalizeModuleMapPath(SmallVectorImpl<char> &Path) {
+  FileManager &FM = SourceMgr.getFileManager();
+  FM.makeAbsolutePath(Path);
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jansvoboda11 wrote:

I don't understand how would this impact explicit module invocations? These can still use relative module map paths, it's just that the compiler will use the absolute canonical path internally (IIUC in an non-observable way).

https://github.com/llvm/llvm-project/pull/66389