[clang] [flang] [flang][cuda] Add -fcuda option (PR #84944)

[Valentin Clement バレンタイン クレメン via cfe-commits]

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@@ -6488,6 +6488,9 @@ defm stack_arrays : BoolOptionWithoutMarshalling<"f", "stack-arrays",
 defm loop_versioning : BoolOptionWithoutMarshalling<"f", "version-loops-for-stride",
   PosFlag<SetTrue, [], [ClangOption], "Create unit-strided versions of loops">,
    NegFlag<SetFalse, [], [ClangOption], "Do not create unit-strided loops (default)">>;
+
+def fcuda : Flag<["-"], "fcuda">, Group<f_Group>,
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clementval wrote:

The alternative is to use the same as `clang` with `-x <language>`. I will need to check if we can filter the language so only the ones meaningful to flang can be passed. 

https://github.com/llvm/llvm-project/pull/84944