3 files changed, 46 insertions, 12 deletions
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index 7671995d609..850308e1477 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -630,14 +630,19 @@ bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range,
        Alloc != AllocEnd; ++Alloc) {
     // Even member operator new/delete are implicitly treated as
     // static, so don't use AddMemberCandidate.
-    if (FunctionDecl *Fn = 
-          dyn_cast<FunctionDecl>((*Alloc)->getUnderlyingDecl())) {
-      AddOverloadCandidate(Fn, Alloc.getAccess(), Args, NumArgs, Candidates,
-                           /*SuppressUserConversions=*/false);
+
+    if (FunctionTemplateDecl *FnTemplate = 
+          dyn_cast<FunctionTemplateDecl>((*Alloc)->getUnderlyingDecl())) {
+      AddTemplateOverloadCandidate(FnTemplate, Alloc.getAccess(),
+                                   /*ExplicitTemplateArgs=*/0, Args, NumArgs,
+                                   Candidates,
+                                   /*SuppressUserConversions=*/false);
       continue;
-    } 
-    
-    // FIXME: Handle function templates
+    }
+
+    FunctionDecl *Fn = cast<FunctionDecl>((*Alloc)->getUnderlyingDecl());
+    AddOverloadCandidate(Fn, Alloc.getAccess(), Args, NumArgs, Candidates,
+                         /*SuppressUserConversions=*/false);
   }
 
   // Do the resolution.
@@ -768,12 +773,16 @@ void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
     DeclContext::lookup_iterator Alloc, AllocEnd;
     for (llvm::tie(Alloc, AllocEnd) = GlobalCtx->lookup(Name);
          Alloc != AllocEnd; ++Alloc) {
-      // FIXME: Do we need to check for default arguments here?
-      FunctionDecl *Func = cast<FunctionDecl>(*Alloc);
-      if (Func->getNumParams() == 1 &&
+      // Only look at non-template functions, as it is the predefined,
+      // non-templated allocation function we are trying to declare here.
+      if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
+        QualType InitialParamType =
           Context.getCanonicalType(
-            Func->getParamDecl(0)->getType().getUnqualifiedType()) == Argument)
-        return;
+            Func->getParamDecl(0)->getType().getUnqualifiedType());
+        // FIXME: Do we need to check for default arguments here?
+        if (Func->getNumParams() == 1 && InitialParamType == Argument)
+          return;
+      }
     }
   }
 
diff --git a/clang/test/SemaCXX/new-delete-predefined-decl.cpp b/clang/test/SemaCXX/new-delete-predefined-decl.cpp
new file mode 100644
index 00000000000..6234b740a47
--- /dev/null
+++ b/clang/test/SemaCXX/new-delete-predefined-decl.cpp
@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -DTEMPLATE_OVERLOAD -fsyntax-only -verify %s
+
+#include <stddef.h>
+
+// Note that each test must be run separately so it can be the first operator
+// new declaration in the file.
+
+#if defined(TEMPLATE_OVERLOAD)
+// Don't crash on global template operator new overloads.
+template<typename T> void* operator new(size_t, T);
+void test_template_overload() {
+  (void)new(0) double;
+}
+#endif
+
+void test_predefined() {
+  (void)new double;
+}
diff --git a/clang/test/SemaCXX/new-delete.cpp b/clang/test/SemaCXX/new-delete.cpp
index b058fc13d96..6f895553431 100644
--- a/clang/test/SemaCXX/new-delete.cpp
+++ b/clang/test/SemaCXX/new-delete.cpp
@@ -216,3 +216,10 @@ static void* f(void* g)
 {
     return new (g) X13();
 }
+
+namespace PR5918 { // Look for template operator new overloads.
+  struct S { template<typename T> static void* operator new(size_t, T); };
+  void test() {
+    (void)new(0) S;
+  }
+}