Fix PR26152.

Fix the condition for when the new global takes over the name of
the existing one to be the negation of the condition for the new
global to get internal linkage.

llvm-svn: 258355

llvm/lib/Linker/IRMover.cpp

@@ -1087,7 +1087,7 @@ Constant *IRLinker::linkGlobalValueProto(GlobalValue *SGV, bool ForAlias) {
       return nullptr;
 
     NewGV = copyGlobalValueProto(SGV, ShouldLink);
-    if (!ForAlias)
+    if (ShouldLink || !ForAlias)
       forceRenaming(NewGV, SGV->getName());
   }
   if (ShouldLink || ForAlias) {

llvm/test/Linker/Inputs/alias-2.ll

@@ -0,0 +1,7 @@
+define void @B() {
+  call void @A()
+  ret void
+}
+
+declare void @A()
+

llvm/test/Linker/alias-2.ll

@@ -0,0 +1,24 @@
+; RUN: llvm-link %s %S/Inputs/alias-2.ll -S -o - | FileCheck %s
+; RUN: llvm-link %S/Inputs/alias-2.ll %s -S -o - | FileCheck %s
+
+; Test the fix for PR26152, where A from the second module is
+; erroneously renamed to A.1 and not linked to the declaration from
+; the first module
+
+@C = alias void (), void ()* @A
+
+define void @D() {
+  call void @C()
+  ret void
+}
+
+define void @A() {
+  ret void
+}
+
+; CHECK-DAG: @C = alias void (), void ()* @A
+; CHECK-DAG: define void @B()
+; CHECK-DAG:   call void @A()
+; CHECK-DAG: define void @D()
+; CHECK-DAG:   call void @C()
+; CHECK-DAG: define void @A()