[clang] [flang] [llvm] [flang] Improvise the error message for the option "-fconvert" with allowed values (PR #215966)

[Kiran Kumar T P via llvm-commits]

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@@ -20,10 +22,17 @@
 ! RUN: %flang_fc1 -emit-mlir -fconvert=big-endian %s -o - | FileCheck %s --check-prefix=VALID_FC1
 ! RUN: %flang_fc1 -emit-mlir -fconvert=swap %s -o - | FileCheck %s --check-prefix=VALID_FC1
 ! RUN: not %flang_fc1 -fconvert=foobar %s  2>&1 | FileCheck %s --check-prefix=INVALID
+! RUN: not %flang_fc1 -fconvert=big_endian %s  2>&1 | FileCheck %s --check-prefix=INVALID-BIG-ENDIAN
+! RUN: not %flang_fc1 -fconver=Foobar %s  2>&1 | FileCheck %s --check-prefix=UNKNOWN-OPTION
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kiranktp wrote:

Agree. I would remove the same.

https://github.com/llvm/llvm-project/pull/215966