[clang] [clang] Respect field alignment in layout compatibility of structs (PR #84313)

[via cfe-commits]

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@@ -19185,7 +19185,8 @@ static bool isLayoutCompatible(ASTContext &C, EnumDecl *ED1, EnumDecl *ED2) {
 
 /// Check if two fields are layout-compatible.
 static bool isLayoutCompatible(ASTContext &C, FieldDecl *Field1,
-                               FieldDecl *Field2) {
+                               FieldDecl *Field2,
+                               bool IgnoreAlignment = false) {
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cor3ntin wrote:

I think I would prefer calling that `IsUnionMember` or something like that (and reverse the condition everywhere)

https://github.com/llvm/llvm-project/pull/84313