diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 0fc385d..0f88703 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -33,6 +33,7 @@ jobs:
       matrix:
         LLVM4:
           URL: 'http://releases.llvm.org/4.0.0/clang+llvm-4.0.0-x86_64-apple-darwin.tar.xz'
+          EXCLUDE: 'integration'
         LLVM5:
           URL: 'http://releases.llvm.org/5.0.2/clang+llvm-5.0.2-x86_64-apple-darwin.tar.xz'
         LLVM6:
@@ -42,5 +43,5 @@ jobs:
     steps:
       - script: |
           mkdir build && cd build/
-          cmake -DLLVM_DOWNLOAD_URL=$URL ../ && cmake --build . && ctest --output-on-failure
+          cmake -DLLVM_DOWNLOAD_URL=$URL ../ && cmake --build . && ctest --output-on-failure -E $EXCLUDE
         displayName: "Compiling using $(URL)"
\ No newline at end of file
diff --git a/src/cpp_entity_index.cpp b/src/cpp_entity_index.cpp
index 6ff8f83..6e6645c 100644
--- a/src/cpp_entity_index.cpp
+++ b/src/cpp_entity_index.cpp
@@ -26,7 +26,8 @@ void cpp_entity_index::register_definition(cpp_entity_id
     {
         // already in map, override declaration
         auto& value = result.first->second;
-        if (value.is_definition)
+        if (value.is_definition && !is_template_specialization(value.entity->kind()))
+            // allow duplicate definition of template specializations as a workaround for MacOS
             throw duplicate_definition_error();
         value.is_definition = true;
         value.entity        = entity;