Index: lib/CodeGen/ManagedMemoryRewrite.cpp
===================================================================
--- lib/CodeGen/ManagedMemoryRewrite.cpp
+++ lib/CodeGen/ManagedMemoryRewrite.cpp
@@ -102,6 +102,7 @@
       Function *PollyMallocManaged = GetOrCreatePollyMallocManaged(M);
       assert(PollyMallocManaged && "unable to create polly_mallocManaged");
       Malloc->replaceAllUsesWith(PollyMallocManaged);
+      Malloc->eraseFromParent();
     }
 
     Function *Free = M.getFunction("free");
@@ -110,6 +111,7 @@
       Function *PollyFreeManaged = GetOrCreatePollyFreeManaged(M);
       assert(PollyFreeManaged && "unable to create polly_freeManaged");
       Free->replaceAllUsesWith(PollyFreeManaged);
+      Free->eraseFromParent();
     }
 
     return true;
Index: test/GPGPU/managed-memory-rewrite-malloc-free.ll
===================================================================
--- test/GPGPU/managed-memory-rewrite-malloc-free.ll
+++ test/GPGPU/managed-memory-rewrite-malloc-free.ll
@@ -41,6 +41,10 @@
 ; HOST-IR  call void @polly_freeManaged(i8* %toFreeBitcast)
 ; HOST-IR: declare void @polly_freeManaged(i8*)
 
+; // Check that we remove the original malloc,free
+; HOST-IR-NOT: declare i8* @malloc(i64)
+; HOST-IR-NOT: declare void @free(i8*)
+
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.12.0"