[clang] [llvm] Enable fexec-charset option (PR #138895)

[Sergei Barannikov via cfe-commits]

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@@ -0,0 +1,46 @@
+// RUN: %clang %s -std=c++17 -emit-llvm -S -target s390x-ibm-zos -o - | FileCheck %s
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s-barannikov wrote:

Will it look much worse if autogenerate the check lines using `update_cc_test_checks.py --check-globals`?

https://github.com/llvm/llvm-project/pull/138895