[clang] [flang] [flang][Driver] Support -print-supported-extensions (PR #117402)

[Andrzej Warzyński via cfe-commits]

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@@ -0,0 +1,34 @@
+! REQUIRES: arm-registered-target
+
+! RUN: %flang --target=arm-linux-gnu --print-supported-extensions 2>&1 \
+! RUN:   | FileCheck --strict-whitespace --implicit-check-not=FEAT_ %s
+
+! CHECK: All available -march extensions for ARM
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banach-space wrote:

IMO, it would be sufficient to only test this line and refer folks to Clang for the rest. Just to avoid duplicating tests. WDYT?

For options like this one, we should have one test file shared between Clang and Flang. That would probably have to live outside of Flang and Clang. Worth considering for the future.

https://github.com/llvm/llvm-project/pull/117402