diff --git a/include/xlnt/worksheet/phonetic_pr.hpp b/include/xlnt/worksheet/phonetic_pr.hpp
index 592cb8e8..74561f9c 100644
--- a/include/xlnt/worksheet/phonetic_pr.hpp
+++ b/include/xlnt/worksheet/phonetic_pr.hpp
@@ -38,7 +38,7 @@ namespace xlnt {
 class XLNT_API phonetic_pr
 {
 public:
-    static const std::string Serialised_ID;
+    static std::string Serialised_ID();
 
     /// <summary>
     /// possible values for alignment property
diff --git a/source/CMakeLists.txt b/source/CMakeLists.txt
index 739d2c5a..24daabcc 100644
--- a/source/CMakeLists.txt
+++ b/source/CMakeLists.txt
@@ -46,6 +46,7 @@ elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-float-equal") # don't warn on uses of == for fp types
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-newline-eof") # no longer an issue with post-c++11 standards which mandate include add a newline if neccesary
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-covered-switch-default") # default is often added to switches for completeness or to cover future alternatives
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-exit-time-destructors") # this is just a warning to notify that the destructor will run during exit
 endif()
 
 if(STATIC_CRT)
diff --git a/source/detail/serialization/xlsx_producer.cpp b/source/detail/serialization/xlsx_producer.cpp
index d2c27a92..5d854d7d 100644
--- a/source/detail/serialization/xlsx_producer.cpp
+++ b/source/detail/serialization/xlsx_producer.cpp
@@ -2749,7 +2749,7 @@ void xlsx_producer::write_worksheet(const relationship &rel)
 
     if (ws.has_phonetic_properties())
     {
-        write_start_element(xmlns, phonetic_pr::Serialised_ID);
+        write_start_element(xmlns, phonetic_pr::Serialised_ID());
         const auto &ph_props = ws.phonetic_properties();
         write_attribute("fontId", ph_props.font_id());
         if (ph_props.has_type())
@@ -2760,7 +2760,7 @@ void xlsx_producer::write_worksheet(const relationship &rel)
         {
             write_attribute("alignment", phonetic_pr::alignment_as_string(ph_props.alignment()));
         }
-        write_end_element(xmlns, phonetic_pr::Serialised_ID);
+        write_end_element(xmlns, phonetic_pr::Serialised_ID());
     }
 
     if (ws.has_page_margins())
diff --git a/source/worksheet/phonetic_pr.cpp b/source/worksheet/phonetic_pr.cpp
index 602fa01c..f046fa58 100644
--- a/source/worksheet/phonetic_pr.cpp
+++ b/source/worksheet/phonetic_pr.cpp
@@ -25,14 +25,13 @@
 #include <array>
 namespace {
 // Order of elements defined by phonetic_pr::Type enum
-const std::array<std::string, 4>& Types()
+const std::array<std::string, 4> &Types()
 {
     static const std::array<std::string, 4> types{
-        "fullwidthKatakana",
-        "halfwidthKatakana",
-        "Hiragana",
-        "noConversion"
-    };
+        std::string("fullwidthKatakana"),
+        std::string("halfwidthKatakana"),
+        std::string("Hiragana"),
+        std::string("noConversion")};
     return types;
 }
 
@@ -40,10 +39,10 @@ const std::array<std::string, 4>& Types()
 const std::array<std::string, 4> &Alignments()
 {
     static const std::array<std::string, 4> alignments{
-        "Center",
-        "Distributed",
-        "Left",
-        "NoControl"};
+        std::string("Center"),
+        std::string("Distributed"),
+        std::string("Left"),
+        std::string("NoControl")};
     return alignments;
 }
 
@@ -53,7 +52,10 @@ namespace xlnt {
 /// <summary>
 /// out of line initialiser for static const member
 /// </summary>
-const std::string phonetic_pr::Serialised_ID = "phoneticPr";
+std::string phonetic_pr::Serialised_ID()
+{
+    return "phoneticPr";
+}
 
 phonetic_pr::phonetic_pr(font_id_t font)
     : font_id_(font)
@@ -62,7 +64,7 @@ phonetic_pr::phonetic_pr(font_id_t font)
 
 void phonetic_pr::serialise(std::ostream &output_stream) const
 {
-    output_stream << '<' << Serialised_ID << R"( fontID=")" << std::to_string(font_id_) << '"';
+    output_stream << '<' << Serialised_ID() << R"( fontID=")" << std::to_string(font_id_) << '"';
     if (has_type())
     {
         output_stream << R"( type=")" << type_as_string(type_.get()) << '"';
@@ -117,7 +119,7 @@ void phonetic_pr::alignment(align align)
 // serialisation
 const std::string &phonetic_pr::type_as_string(phonetic_pr::phonetic_type type)
 {
-    return Types()[static_cast<int>(type)];
+    return Types()[static_cast<std::size_t>(type)];
 }
 
 phonetic_pr::phonetic_type phonetic_pr::type_from_string(const std::string &str)
@@ -134,7 +136,7 @@ phonetic_pr::phonetic_type phonetic_pr::type_from_string(const std::string &str)
 
 const std::string &phonetic_pr::alignment_as_string(align type)
 {
-    return Alignments()[static_cast<int>(type)];
+    return Alignments()[static_cast<std::size_t>(type)];
 }
 
 phonetic_pr::align phonetic_pr::alignment_from_string(const std::string &str)
diff --git a/source/worksheet/worksheet.cpp b/source/worksheet/worksheet.cpp
index 9d59e895..5ab28fa1 100644
--- a/source/worksheet/worksheet.cpp
+++ b/source/worksheet/worksheet.cpp
@@ -98,7 +98,7 @@ void worksheet::create_named_range(const std::string &name, const range_referenc
             throw invalid_parameter(); //("named range name must be outside the range A1-XFD1048576");
         }
     }
-    catch (xlnt::invalid_cell_reference)
+    catch (xlnt::invalid_cell_reference&)
     {
         // name is not a valid reference, that's good
     }