[clang] [flang] [flang] Add -fcomplex-arithmetic= option and select complex division algorithm (PR #146641)

[Tarun Prabhu via cfe-commits]

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@@ -484,6 +484,21 @@ static void parseCodeGenArgs(Fortran::frontend::CodeGenOptions &opts,
   }
 
   parseDoConcurrentMapping(opts, args, diags);
+
+  if (const auto *arg =
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tarunprabhu wrote:

Could we use a concrete type instead of `auto` here?

https://github.com/llvm/llvm-project/pull/146641