From 520bc229eaad5a506af0326668716883a97bc686 Mon Sep 17 00:00:00 2001
From: Christian Kamm <kamm@incasoftware.de>
Date: Sun, 8 Mar 2009 16:21:11 +0100
Subject: [PATCH] Give compile units LinkOnceLinkage to circumvent duplicate
 symbols with LLVM linking.

---
 gen/todebug.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/gen/todebug.cpp b/gen/todebug.cpp
index 9b969b87..f856d703 100644
--- a/gen/todebug.cpp
+++ b/gen/todebug.cpp
@@ -500,6 +500,12 @@ llvm::DICompileUnit DtoDwarfCompileUnit(Module* m)
         false, // isMain,
         false // isOptimized
     );
+    
+    // if the linkage stays internal, we can't llvm-link the generated modules together:
+    // llvm's DwarfWriter uses path and filename to determine the symbol name and we'd
+    // end up with duplicate symbols
+    m->ir.irModule->diCompileUnit.getGV()->setLinkage(llvm::GlobalValue::LinkOnceLinkage);
+    m->ir.irModule->diCompileUnit.getGV()->setName(std::string("llvm.dbg.compile_unit_") + srcpath + m->srcfile->name->toChars());
 
     return m->ir.irModule->diCompileUnit;
 }