[clang] [flang] [flang][Driver] Enable -pie and -no-pie in flang's driver (PR #164890)

[Tarun Prabhu via cfe-commits]

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@@ -10,6 +10,16 @@
 ! Make sure that `-L' is "visible" to Flang's driver
 ! RUN: %flang -L/ -### %s
 
+! Check that '-pie' is "visible" to Flang's driver and is passed on to the
+! linker.
+! RUN: %flang -pie -### %s 2>&1 | FileCheck %s --check-prefix=PIE
+! PIE: "-pie"
+
+! Check that '-no-pie' is "visible" to Flang's driver and that "-pie" is *not*
+! passed to the linker.
+! RUN: %flang -no-pie -### %s 2>&1 | FileCheck %s --check-prefix=NO-PIE
+! NO-PIE-NOT: "-pie"
+
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tarunprabhu wrote:

The default is `-pie`. There is an explicit test for this now. Tests have also been added for the combination.

https://github.com/llvm/llvm-project/pull/164890