[clang] [llvm] [mlir] [support] Use VFS in `SourceMgr` for loading includes (PR #162903)

[Jan Svoboda via cfe-commits]

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@@ -378,8 +378,10 @@ struct SourceMgrDiagnosticHandlerImpl {
     }
 
     // Otherwise, try to load the source file.
-    std::string ignored;
-    unsigned id = mgr.AddIncludeFile(std::string(filename), SMLoc(), ignored);
+    auto bufferOrErr = llvm::MemoryBuffer::getFile(filename);
+    if (!bufferOrErr)
+      return 0;
+    unsigned id = mgr.AddNewSourceBuffer(std::move(*bufferOrErr), SMLoc());
     filenameToBufId[filename] = id;
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jansvoboda11 wrote:

Ah, that makes sense, sorry for the breakage. With https://github.com/llvm/llvm-project/pull/163862 this is no longer necessary. Fix is here: https://github.com/llvm/llvm-project/pull/164464.

https://github.com/llvm/llvm-project/pull/162903