[llvm] [SystemZ][z/OS] Implement executePostLayoutBinding for GOFFObjectWriter (PR #67868)

[via llvm-commits]

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@@ -10,6 +10,7 @@
 #define LLVM_MC_MCGOFFOBJECTWRITER_H
 
 #include "llvm/MC/MCObjectWriter.h"
+#include "llvm/Support/Casting.h"
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diggerlin wrote:

we can put #include "llvm/Support/Casting.h" in llvm/lib/MC/GOFFObjectWriter.cpp

https://github.com/llvm/llvm-project/pull/67868