[clang] [flang] [flang][driver] add -flang-deprecated-no-hlfir hidden option (PR #71820)

[Tom Eccles via cfe-commits]

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@@ -1073,6 +1073,12 @@ bool CompilerInvocation::createFromArgs(
     res.loweringOpts.setLowerToHighLevelFIR(true);
   }
 
+  // -flang-deprecated-no-hlfir
+  if (args.hasArg(clang::driver::options::OPT_flang_deprecated_no_hlfir) &&
+      !args.hasArg(clang::driver::options::OPT_emit_hlfir)) {
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tblah wrote:

nit: specifying -flang-depricated-nohlfir and -flang-experimental-hlfir together should probably be an error or at least a warning

https://github.com/llvm/llvm-project/pull/71820