[clang] [Clang] Add `-fdefault-generic-addrspace` flag for targeting GPUs (PR #115777)

[Matt Arsenault via cfe-commits]

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@@ -1579,7 +1579,7 @@ NamedDecl *Sema::getCurFunctionOrMethodDecl() const {
 }
 
 LangAS Sema::getDefaultCXXMethodAddrSpace() const {
-  if (getLangOpts().OpenCL)
+  if (getLangOpts().OpenCL || getLangOpts().OpenCLGenericAddressSpace)
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arsenm wrote:

I think this whole thing is just working around a defect in how OpenCL was implemented. There should be no difference between generic and default address space 

https://github.com/llvm/llvm-project/pull/115777