[llvm] [M68k] Fix ODR violation in GISel code (PR #72797)

[Nikita Popov via llvm-commits]

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@@ -25,6 +25,11 @@
 
 using namespace llvm;
 
+struct M68kFormalArgHandler : public M68kIncomingValueHandler {
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nikic wrote:

This should be wrapped into an anonymous namespace `namespace { }`, so it doesn't get exported.

https://github.com/llvm/llvm-project/pull/72797