When IRgen refers to a function declaration that is not a definition,

and we later find the definition, make sure that we add the definition
(not the declaration) to the list of deferred definitions to
emit. Fixes PR8864.

Thanks to Nick Lewycky for testing this	patch out



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@125157 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CodeGenModule.cpp

@@ -857,10 +857,10 @@ CodeGenModule::GetOrCreateLLVMFunction(llvm::StringRef MangledName,
       if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
         if (FD->isImplicit() && !ForVTable) {
           assert(FD->isUsed() && "Sema didn't mark implicit function as used!");
-          DeferredDeclsToEmit.push_back(D);
+          DeferredDeclsToEmit.push_back(D.getWithDecl(FD));
           break;
         } else if (FD->isThisDeclarationADefinition()) {
-          DeferredDeclsToEmit.push_back(D);
+          DeferredDeclsToEmit.push_back(D.getWithDecl(FD));
           break;
         }
       }

lib/CodeGen/GlobalDecl.h

@@ -81,6 +81,12 @@ public:
     GD.Value.setFromOpaqueValue(P);
     return GD;
   }
+  
+  GlobalDecl getWithDecl(const Decl *D) {
+    GlobalDecl Result(*this);
+    Result.Value.setPointer(D);
+    return Result;
+  }
 };
 
 } // end namespace CodeGen

test/CodeGenCXX/friend-redecl.cpp

@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -triple i386-pc-linux-gnu -emit-llvm %s -o - | FileCheck %s
+// PR8864
+
+struct Foo {
+  friend bool TryFoo(Foo *f2) { return TryFoo(0, f2); }
+
+// CHECK: define{{.*}}Z6TryFooP3Foo
+// CHECK-NOT: ret
+// CHECK: call{{.*}}Z6TryFooiP3Foo
+// CHECK: ret
+
+  friend bool TryFoo(int, Foo *f3);
+};
+bool TryFoo(Foo *f5);
+int main(void) {
+  Foo f;
+  TryFoo(&f);
+}