[clang] [llvm] [llvm] Support llvm::Any across shared libraries on windows (PR #108051)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -28,12 +28,24 @@
 #include "clang/Analysis/FlowSensitive/MatchSwitch.h"
 #include "clang/Analysis/FlowSensitive/TypeErasedDataflowAnalysis.h"
 #include "clang/Analysis/FlowSensitive/WatchedLiteralsSolver.h"
+#include "clang/Support/Compiler.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/STLFunctionalExtras.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/Error.h"
 
+namespace clang {
+namespace dataflow {
+class NoopLattice;
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ymand wrote:

Why is this forward declaration placed in this file, when the NoopLattice is defined in its own file? Regardless, if it does belong here, please comment to explain the intent. I'm a code owner and yet I don't understand what this is doing and how/what I should do to prevent it from breaking in the case of changes. IIUC, this change is Window-specific and seems fragile, making it all the more critical to clearly document.

https://github.com/llvm/llvm-project/pull/108051