[PATCH] D75277: [WebAssembly] Remove restriction on main name mangling

[Sam Clegg via Phabricator via llvm-commits]

sbc100 added inline comments.


================
Comment at: clang/lib/CodeGen/CodeGenModule.cpp:6360
+      auto *GA = llvm::GlobalAlias::create("__main_void", F);
+      GA->setVisibility(F->getVisibility());
+    }
----------------
sunfish wrote:
> sbc100 wrote:
> > sunfish wrote:
> > > Can this use `GA->setVisibility(GlobalValue::HiddenVisibility)`? `__main_void` is an implementation detail, so in theory users shouldn't be setting interesting visibility attributes on it.
> > The caller main / __main_void could live in different shared library the main function itself.  
> > 
> > IIRC the caller of `main` is normally something like crt1.o and it should be able to see `__main_void` if, and only if, it can see `main`.  i.e. if should have the same visibility as main itself, no?
> Typically crt1.o is linked into the same exe/dso as `main`, so it needs `main` to have external linkage, but it doesn't need `main` to have any particular visibility.
> 
> In Emscripten, is `main` being called from a different dso, or from JS following visibility rules for different dsos?
No, emscirpten is not different that respect.   Typically main lives in the same DSO as crt1.o.   

But it doesn't have to, and we have a few tests that check it can be in a separate dso.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75277/new/

https://reviews.llvm.org/D75277