[clang] [CIR] Handle NullStmt (PR #134889)

[Andy Kaylor via cfe-commits]

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@@ -57,6 +57,7 @@ mlir::LogicalResult CIRGenFunction::emitStmt(const Stmt *s,
 
   switch (s->getStmtClass()) {
   case Stmt::BreakStmtClass:
+  case Stmt::NullStmtClass:
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andykaylor wrote:

I just looked at classic codegen. It puts NoStmtClass (along with CXXCatchStmtClass, SEHExceptStmtClass, SEHFinallyStmtClass, and MSDependentExistsStmtClass) in a different group just above this that leads to `llvm_unreachable("invalid statement class to emit generically");` rather than `llvm_unreachable("should have emitted these statements as simple");` as we have here. I can still do that here if you want, but it's currently in the group below that goes to an NYI error.

https://github.com/llvm/llvm-project/pull/134889