Handle weak_extern in the JIT. This fixes
SingleSource/UnitTests/2007-04-25-weak.c in JIT mode. The test
now passes on systems which are able to produce a correct
reference output to compare with.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61674 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ExecutionEngine/JIT/JIT.cpp b/lib/ExecutionEngine/JIT/JIT.cpp
index 5d5ecc4..6cd1c50 100644
--- a/lib/ExecutionEngine/JIT/JIT.cpp
+++ b/lib/ExecutionEngine/JIT/JIT.cpp
@@ -509,16 +509,17 @@
            << "' from bitcode file: " << ErrorMsg << "\n";
       abort();
     }
-  }
 
-  if (void *Addr = getPointerToGlobalIfAvailable(F)) {
-    return Addr;
+    // Now retry to get the address.
+    if (void *Addr = getPointerToGlobalIfAvailable(F))
+      return Addr;
   }
 
   MutexGuard locked(lock);
 
   if (F->isDeclaration()) {
-    void *Addr = getPointerToNamedFunction(F->getName());
+    bool AbortOnFailure = F->getLinkage() != GlobalValue::ExternalWeakLinkage;
+    void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
     addGlobalMapping(F, Addr);
     return Addr;
   }