[clang] [flang] [mlir] [flang,acc] Support -ffp-maxmin-behavior option in lowering. (PR #184730)

[Tarun Prabhu via cfe-commits]

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@@ -16,5 +16,6 @@ end program p
 ! flang driver does not forward the option to -fc1 (fc1-only option)
 ! RUN: not %flang -### -ffp-maxmin-behavior=legacy %s 2>&1 \
 ! RUN:   | FileCheck %s -check-prefix=DRIVER-NO-FORWARD
+! DRIVER-NO-FORWARD: error: unknown argument '-ffp-maxmin-behavior=legacy'
 ! DRIVER-NO-FORWARD: "-fc1"
 ! DRIVER-NO-FORWARD-NOT: -ffp-maxmin-behavior
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tarunprabhu wrote:

Since this is an error, we don't need these checks. It may be a good idea to name the label something more appropriate, maybe `DRIVER-UNKNOWN-ARG` or something like that.

https://github.com/llvm/llvm-project/pull/184730