[clang] [flang][Driver] Support -rpath, -shared, and -static in the frontend (PR #66702)

[Fangrui Song via cfe-commits]

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@@ -50,3 +50,19 @@
 ! MSVC-SAME: FortranDecimal.lib
 ! MSVC-SAME: /subsystem:console
 ! MSVC-SAME: "[[object_file]]"
+
+! Verify that certain linker flags are known to the frontend and are passed on
+! to the linker.
+
+! RUN: %flang -### -rpath /path/to/dir %s 2>&1 \
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MaskRay wrote:

Consider using one command to test many options that can be used together.

Note that you can also use -static -shared together: 408e6de8c09fc7e71329199947e977fe1c40caf1 , so I'm fine if you use one line for -shared and another for -static :)

https://github.com/llvm/llvm-project/pull/66702