diff --git a/include/orcus/tokens.hpp b/include/orcus/tokens.hpp
index 9edc8771068a7b8d8b753307f82c9a1e8975b34a..fde4b924d4e15519406097654288f1941686c988 100644
--- a/include/orcus/tokens.hpp
+++ b/include/orcus/tokens.hpp
@@ -31,7 +31,7 @@ class ORCUS_PSR_DLLPUBLIC tokens
 public:
     tokens() = delete;
     tokens(const tokens&) = delete;
-    tokens(const char** token_names, size_t token_name_count);
+    tokens(const char* const* token_names, size_t token_name_count);
     ~tokens();
 
     /**
@@ -64,7 +64,7 @@ private:
     using token_map_type = std::unordered_map<std::string_view, xml_token_t>;
 
     token_map_type m_tokens;
-    const char** m_token_names;
+    const char* const* m_token_names;
     size_t m_token_name_count;
 };
 
diff --git a/misc/xml-tokens/gen-odf-tokens.py b/misc/xml-tokens/gen-odf-tokens.py
index 2838604b74b1f53c909e6a86c9fdd651b1ebc017..af83ed80ca2b76efbfe4d03a29e607e6a3de515b 100755
--- a/misc/xml-tokens/gen-odf-tokens.py
+++ b/misc/xml-tokens/gen-odf-tokens.py
@@ -98,7 +98,7 @@ def gen_namespace_tokens(filepath, ns_values):
         outfile.write("extern const xmlns_id_t NS_odf_")
         outfile.write(key)
         outfile.write(";\n")
-    outfile.write("\nextern const xmlns_id_t* NS_odf_all;\n")
+    outfile.write("\nextern const xmlns_id_t* const NS_odf_all;\n")
     outfile.write("\n}\n\n")
     outfile.close()
 
@@ -125,7 +125,7 @@ def gen_namespace_tokens(filepath, ns_values):
     outfile.write("};\n\n")
     outfile.write("} // anonymous\n\n")
 
-    outfile.write("const xmlns_id_t* NS_odf_all = odf_ns;\n\n")
+    outfile.write("const xmlns_id_t* const NS_odf_all = odf_ns;\n\n")
 
     outfile.write("}\n\n")
     outfile.close()
diff --git a/misc/xml-tokens/token_util.py b/misc/xml-tokens/token_util.py
index 19ba4369e7760aaa200ff062a76bda1b05ece457..ddf637ace177f5763c3466e2aa832569e5831b10 100644
--- a/misc/xml-tokens/token_util.py
+++ b/misc/xml-tokens/token_util.py
@@ -57,7 +57,7 @@ def gen_token_names(outfile, tokens):
         print(get_auto_gen_warning(), file=f)
         print(file=f)
 
-        print("const char* token_names[] = {", file=f)
+        print("const char* const token_names[] = {", file=f)
         print(f"    \"{unknown_token_name}\", // 0", file=f)
 
         for i, token in enumerate(tokens):
@@ -67,4 +67,4 @@ def gen_token_names(outfile, tokens):
             print(f"    \"{token}\"{s} // {i+1}", file=f)
         print("};", file=f)
         print(file=f)
-        print(f"size_t token_name_count = {len(tokens)+1};", file=f)
+        print(f"const size_t token_name_count = {len(tokens)+1};", file=f)
diff --git a/src/liborcus/gnumeric_namespace_types.cpp b/src/liborcus/gnumeric_namespace_types.cpp
index 1ff0ec9767ffea32767ea4991174418d7a7a4949..91c97c8f8c6a410501e8c2c0d4f8daa56c28d41c 100644
--- a/src/liborcus/gnumeric_namespace_types.cpp
+++ b/src/liborcus/gnumeric_namespace_types.cpp
@@ -18,7 +18,7 @@ const xmlns_id_t NS_gnumeric_xsi = "http://www.w3.org/2001/XMLSchema-instance";
 
 namespace {
 
-xmlns_id_t gnumeric_ns[] = {
+const xmlns_id_t gnumeric_ns[] = {
     NS_gnumeric_dc,
     NS_gnumeric_gnm,
     NS_gnumeric_ooo,
@@ -32,7 +32,7 @@ xmlns_id_t gnumeric_ns[] = {
 
 }
 
-const xmlns_id_t* NS_gnumeric_all = gnumeric_ns;
+const xmlns_id_t* const NS_gnumeric_all = gnumeric_ns;
 
 }
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/src/liborcus/gnumeric_namespace_types.hpp b/src/liborcus/gnumeric_namespace_types.hpp
index 2d6b7ab2e44c99af90f363d09d2d3c66d48b2fc9..4fa89fc86deee02662aa31ccdc6c355ef32db825 100644
--- a/src/liborcus/gnumeric_namespace_types.hpp
+++ b/src/liborcus/gnumeric_namespace_types.hpp
@@ -18,7 +18,7 @@ extern const xmlns_id_t NS_gnumeric_ooo;
 extern const xmlns_id_t NS_gnumeric_xlink;
 extern const xmlns_id_t NS_gnumeric_xsi;
 
-extern const xmlns_id_t* NS_gnumeric_all;
+extern const xmlns_id_t* const NS_gnumeric_all;
 
 }
 
diff --git a/src/liborcus/gnumeric_tokens.inl b/src/liborcus/gnumeric_tokens.inl
index c20fb69ba9f65363f5ef05f2a0b98209d11e46e3..ecd8e74df9de9c67dcc18684c3e1ddc7e85d5d2e 100644
--- a/src/liborcus/gnumeric_tokens.inl
+++ b/src/liborcus/gnumeric_tokens.inl
@@ -1,6 +1,6 @@
 // This file has been auto-generated.  Do not hand-edit this.
 
-const char* token_names[] = {
+const char* const token_names[] = {
     "??", // 0
     "Active", // 1
     "AllowBlank", // 2
@@ -279,4 +279,4 @@ const char* token_names[] = {
     "width"  // 275
 };
 
-size_t token_name_count = 276;
+const size_t token_name_count = 276;
diff --git a/src/liborcus/odf_namespace_types_cpp.inl b/src/liborcus/odf_namespace_types_cpp.inl
index 8b0dc1ffebc42b8144b692ef2d6146bcb52be4d8..a91959a38bf1d9332b2cb5cae7ae621dd50e1742 100644
--- a/src/liborcus/odf_namespace_types_cpp.inl
+++ b/src/liborcus/odf_namespace_types_cpp.inl
@@ -57,7 +57,7 @@ const xmlns_id_t odf_ns[] = {
 
 } // anonymous
 
-const xmlns_id_t* NS_odf_all = odf_ns;
+const xmlns_id_t* const NS_odf_all = odf_ns;
 
 }
 
diff --git a/src/liborcus/odf_namespace_types_hpp.inl b/src/liborcus/odf_namespace_types_hpp.inl
index a80c9173289a1dc1d6bc3f3470d07faac6925166..75941235454789df1adddbb150fda3b341ede1a8 100644
--- a/src/liborcus/odf_namespace_types_hpp.inl
+++ b/src/liborcus/odf_namespace_types_hpp.inl
@@ -25,7 +25,7 @@ extern const xmlns_id_t NS_odf_xforms;
 extern const xmlns_id_t NS_odf_xhtml;
 extern const xmlns_id_t NS_odf_xlink;
 
-extern const xmlns_id_t* NS_odf_all;
+extern const xmlns_id_t* const NS_odf_all;
 
 }
 
diff --git a/src/liborcus/odf_tokens.inl b/src/liborcus/odf_tokens.inl
index 623c72161603e84d5c6114adcff2deead50bd556..21c856189d0f141b157a6f9e7542b3d13876d557 100644
--- a/src/liborcus/odf_tokens.inl
+++ b/src/liborcus/odf_tokens.inl
@@ -1,6 +1,6 @@
 // This file has been auto-generated.  Do not hand-edit this.
 
-const char* token_names[] = {
+const char* const token_names[] = {
     "??", // 0
     "0", // 1
     "0deg", // 2
@@ -2282,4 +2282,4 @@ const char* token_names[] = {
     "zero-values"  // 2278
 };
 
-size_t token_name_count = 2279;
\ No newline at end of file
+const size_t token_name_count = 2279;
diff --git a/src/liborcus/ods_content_xml_context.cpp b/src/liborcus/ods_content_xml_context.cpp
index bd84b2f8ffb264a6152ad17ccbe9936cc71ac37e..18c56276bb7eaf2274d0bc53849de71cf0fb1c05 100644
--- a/src/liborcus/ods_content_xml_context.cpp
+++ b/src/liborcus/ods_content_xml_context.cpp
@@ -34,7 +34,7 @@ namespace cell_value {
 using map_type = mdds::sorted_string_map<ods_content_xml_context::cell_value_type>;
 
 // Keys must be sorted.
-map_type::entry_type entries[] = {
+constexpr map_type::entry_type entries[] = {
     { "date",   ods_content_xml_context::vt_date },
     { "float",  ods_content_xml_context::vt_float },
     { "string", ods_content_xml_context::vt_string }
diff --git a/src/liborcus/ooxml_content_types.cpp b/src/liborcus/ooxml_content_types.cpp
index eb614c7b45abb9e106eba118f3b3f79d8ffcfca8..13e78d15130dbccdd46d04281e00b729784209f7 100644
--- a/src/liborcus/ooxml_content_types.cpp
+++ b/src/liborcus/ooxml_content_types.cpp
@@ -37,7 +37,7 @@ const content_type_t CT_image_png                   = "image/png";
 
 namespace {
 
-content_type_t cts[] = {
+const content_type_t cts[] = {
     CT_ooxml_extended_properties,
     CT_ooxml_drawing,
     CT_ooxml_vml_drawing,
@@ -68,7 +68,7 @@ content_type_t cts[] = {
 
 }
 
-const content_type_t* CT_all = cts;
+const content_type_t* const CT_all = cts;
 
 }
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/src/liborcus/ooxml_content_types.hpp b/src/liborcus/ooxml_content_types.hpp
index d82dd53fbd793030ee330af8e060e07d9988445b..af8ab7c7b26d51e3d9232a8760130d7ebb310db8 100644
--- a/src/liborcus/ooxml_content_types.hpp
+++ b/src/liborcus/ooxml_content_types.hpp
@@ -41,7 +41,7 @@ extern const content_type_t CT_image_png;
 /**
  * Null-terminated array of all content types.
  */
-extern const content_type_t* CT_all;
+extern const content_type_t* const CT_all;
 
 }
 
diff --git a/src/liborcus/ooxml_namespace_types.cpp b/src/liborcus/ooxml_namespace_types.cpp
index 8c1224b253dcee83d4d73b49055515154bf34c5b..31b26d2d091aad00c71a51c2bf74397806a99ae7 100644
--- a/src/liborcus/ooxml_namespace_types.cpp
+++ b/src/liborcus/ooxml_namespace_types.cpp
@@ -22,7 +22,7 @@ const xmlns_id_t NS_mso_x14 = "http://schemas.microsoft.com/office/spreadsheetml
 
 namespace {
 
-xmlns_id_t ooxml_ns[] = {
+const xmlns_id_t ooxml_ns[] = {
     NS_ooxml_a,
     NS_ooxml_r,
     NS_ooxml_xdr,
@@ -30,13 +30,13 @@ xmlns_id_t ooxml_ns[] = {
     nullptr
 };
 
-xmlns_id_t opc_ns[] = {
+const xmlns_id_t opc_ns[] = {
     NS_opc_ct,
     NS_opc_rel,
     nullptr
 };
 
-xmlns_id_t misc_ns[] = {
+const xmlns_id_t misc_ns[] = {
     NS_mc,
     NS_mso_x14,
     nullptr
@@ -44,9 +44,9 @@ xmlns_id_t misc_ns[] = {
 
 }
 
-const xmlns_id_t* NS_ooxml_all = ooxml_ns;
-const xmlns_id_t* NS_opc_all = opc_ns;
-const xmlns_id_t* NS_misc_all = misc_ns;
+const xmlns_id_t* const NS_ooxml_all = ooxml_ns;
+const xmlns_id_t* const NS_opc_all = opc_ns;
+const xmlns_id_t* const NS_misc_all = misc_ns;
 
 }
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/src/liborcus/ooxml_namespace_types.hpp b/src/liborcus/ooxml_namespace_types.hpp
index 8183bf89714e67f841b409497c2ce3390c502d7f..5cd5f519993f1530eb509ad4d99a9f9fb6e6d1ad 100644
--- a/src/liborcus/ooxml_namespace_types.hpp
+++ b/src/liborcus/ooxml_namespace_types.hpp
@@ -26,17 +26,17 @@ extern const xmlns_id_t NS_mso_x14;
 /**
  * Null-terminated array of all ooxml namespaces.
  */
-extern const xmlns_id_t* NS_ooxml_all;
+extern const xmlns_id_t* const NS_ooxml_all;
 
 /**
  * Null-terminated array of all opc namespaces.
  */
-extern const xmlns_id_t* NS_opc_all;
+extern const xmlns_id_t* const NS_opc_all;
 
 /**
  * Null-terminated array of all the other namespaces.
  */
-extern const xmlns_id_t* NS_misc_all;
+extern const xmlns_id_t* const NS_misc_all;
 
 }
 
diff --git a/src/liborcus/ooxml_schemas.cpp b/src/liborcus/ooxml_schemas.cpp
index b0e86e492d4e537996eb131e59a0342ee52f01eb..22364ced9a205bd2eff597fb7f2d381ffc0b8203 100644
--- a/src/liborcus/ooxml_schemas.cpp
+++ b/src/liborcus/ooxml_schemas.cpp
@@ -9,33 +9,33 @@
 
 namespace orcus {
 
-schema_t SCH_mc                           = "http://schemas.openxmlformats.org/markup-compatibility/2006";
-schema_t SCH_opc_content_types            = "http://schemas.openxmlformats.org/package/2006/content-types";
-schema_t SCH_opc_rels                     = "http://schemas.openxmlformats.org/package/2006/relationships";
-schema_t SCH_opc_rels_metadata_core_props = "http://schemas.openxmlformats.org/package/2006/relationships/metadata/core-properties";
-schema_t SCH_od_rels_calc_chain           = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/calcChain";
-schema_t SCH_od_rels_connections          = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/connections";
-schema_t SCH_od_rels_printer_settings     = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/printerSettings";
-schema_t SCH_od_rels_rev_headers          = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/revisionHeaders";
-schema_t SCH_od_rels_rev_log              = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/revisionLog";
-schema_t SCH_od_rels_shared_strings       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/sharedStrings";
-schema_t SCH_od_rels_styles               = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/styles";
-schema_t SCH_od_rels_theme                = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/theme";
-schema_t SCH_od_rels_usernames            = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/usernames";
-schema_t SCH_od_rels_worksheet            = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet";
-schema_t SCH_od_rels_extended_props       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/extended-properties";
-schema_t SCH_od_rels_office_doc           = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument";
-schema_t SCH_od_rels_table                = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/table";
-schema_t SCH_od_rels_pivot_cache_def      = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotCacheDefinition";
-schema_t SCH_od_rels_pivot_cache_rec      = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotCacheRecords";
-schema_t SCH_od_rels_pivot_table          = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotTable";
-schema_t SCH_od_rels_drawing              = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/drawing";
-schema_t SCH_xlsx_main                    = "http://schemas.openxmlformats.org/spreadsheetml/2006/main";
-schema_t SCH_mso_x14ac                    = "http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac";
+const schema_t SCH_mc                           = "http://schemas.openxmlformats.org/markup-compatibility/2006";
+const schema_t SCH_opc_content_types            = "http://schemas.openxmlformats.org/package/2006/content-types";
+const schema_t SCH_opc_rels                     = "http://schemas.openxmlformats.org/package/2006/relationships";
+const schema_t SCH_opc_rels_metadata_core_props = "http://schemas.openxmlformats.org/package/2006/relationships/metadata/core-properties";
+const schema_t SCH_od_rels_calc_chain           = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/calcChain";
+const schema_t SCH_od_rels_connections          = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/connections";
+const schema_t SCH_od_rels_printer_settings     = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/printerSettings";
+const schema_t SCH_od_rels_rev_headers          = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/revisionHeaders";
+const schema_t SCH_od_rels_rev_log              = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/revisionLog";
+const schema_t SCH_od_rels_shared_strings       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/sharedStrings";
+const schema_t SCH_od_rels_styles               = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/styles";
+const schema_t SCH_od_rels_theme                = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/theme";
+const schema_t SCH_od_rels_usernames            = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/usernames";
+const schema_t SCH_od_rels_worksheet            = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet";
+const schema_t SCH_od_rels_extended_props       = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/extended-properties";
+const schema_t SCH_od_rels_office_doc           = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument";
+const schema_t SCH_od_rels_table                = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/table";
+const schema_t SCH_od_rels_pivot_cache_def      = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotCacheDefinition";
+const schema_t SCH_od_rels_pivot_cache_rec      = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotCacheRecords";
+const schema_t SCH_od_rels_pivot_table          = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/pivotTable";
+const schema_t SCH_od_rels_drawing              = "http://schemas.openxmlformats.org/officeDocument/2006/relationships/drawing";
+const schema_t SCH_xlsx_main                    = "http://schemas.openxmlformats.org/spreadsheetml/2006/main";
+const schema_t SCH_mso_x14ac                    = "http://schemas.microsoft.com/office/spreadsheetml/2009/9/ac";
 
 namespace {
 
-schema_t schs[] = {
+const schema_t schs[] = {
     SCH_mc,
     SCH_opc_content_types,
     SCH_opc_rels,
@@ -64,7 +64,7 @@ schema_t schs[] = {
 
 }
 
-schema_t* SCH_all = schs;
+const schema_t* const SCH_all = schs;
 
 }
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/src/liborcus/ooxml_schemas.hpp b/src/liborcus/ooxml_schemas.hpp
index 85adb6f20b18f8fb9b9493f5ca83c248d826faed..bb0c0a06bd1d438529e03f8e805c390f396f72be 100644
--- a/src/liborcus/ooxml_schemas.hpp
+++ b/src/liborcus/ooxml_schemas.hpp
@@ -12,34 +12,34 @@
 
 namespace orcus {
 
-extern schema_t SCH_mc;
-extern schema_t SCH_opc_content_types;
-extern schema_t SCH_opc_rels;
-extern schema_t SCH_opc_rels_metadata_core_props;
-extern schema_t SCH_od_rels_calc_chain;
-extern schema_t SCH_od_rels_connections;
-extern schema_t SCH_od_rels_printer_settings;
-extern schema_t SCH_od_rels_rev_headers;
-extern schema_t SCH_od_rels_rev_log;
-extern schema_t SCH_od_rels_shared_strings;
-extern schema_t SCH_od_rels_styles;
-extern schema_t SCH_od_rels_theme;
-extern schema_t SCH_od_rels_usernames;
-extern schema_t SCH_od_rels_worksheet;
-extern schema_t SCH_od_rels_extended_props;
-extern schema_t SCH_od_rels_office_doc;
-extern schema_t SCH_od_rels_table;
-extern schema_t SCH_od_rels_pivot_cache_def;
-extern schema_t SCH_od_rels_pivot_cache_rec;
-extern schema_t SCH_od_rels_pivot_table;
-extern schema_t SCH_od_rels_drawing;
-extern schema_t SCH_xlsx_main;
-extern schema_t SCH_mso_x14ac;
+const extern schema_t SCH_mc;
+const extern schema_t SCH_opc_content_types;
+const extern schema_t SCH_opc_rels;
+const extern schema_t SCH_opc_rels_metadata_core_props;
+const extern schema_t SCH_od_rels_calc_chain;
+const extern schema_t SCH_od_rels_connections;
+const extern schema_t SCH_od_rels_printer_settings;
+const extern schema_t SCH_od_rels_rev_headers;
+const extern schema_t SCH_od_rels_rev_log;
+const extern schema_t SCH_od_rels_shared_strings;
+const extern schema_t SCH_od_rels_styles;
+const extern schema_t SCH_od_rels_theme;
+const extern schema_t SCH_od_rels_usernames;
+const extern schema_t SCH_od_rels_worksheet;
+const extern schema_t SCH_od_rels_extended_props;
+const extern schema_t SCH_od_rels_office_doc;
+const extern schema_t SCH_od_rels_table;
+const extern schema_t SCH_od_rels_pivot_cache_def;
+const extern schema_t SCH_od_rels_pivot_cache_rec;
+const extern schema_t SCH_od_rels_pivot_table;
+const extern schema_t SCH_od_rels_drawing;
+const extern schema_t SCH_xlsx_main;
+const extern schema_t SCH_mso_x14ac;
 
 /**
  * Null-terminated array of all schema types.
  */
-extern schema_t* SCH_all;
+const extern schema_t* const SCH_all;
 
 }
 
diff --git a/src/liborcus/ooxml_tokens.inl b/src/liborcus/ooxml_tokens.inl
index 5fa2ad0553f2422a98650c19523b8e8c50f43c87..e9a74419a407a8abb7c03b41a6654ddb9484ee7b 100644
--- a/src/liborcus/ooxml_tokens.inl
+++ b/src/liborcus/ooxml_tokens.inl
@@ -1,6 +1,6 @@
 // This file has been auto-generated.  Do not hand-edit this.
 
-const char* token_names[] = {
+const char* const token_names[] = {
     "??", // 0
     "AbbreviatedCaseNumber", // 1
     "Accel", // 2
@@ -3521,4 +3521,4 @@ const char* token_names[] = {
     "zoomToFit"  // 3517
 };
 
-size_t token_name_count = 3518;
\ No newline at end of file
+const size_t token_name_count = 3518;
diff --git a/src/liborcus/opc_context.cpp b/src/liborcus/opc_context.cpp
index e3b1bb57fd372b72c8cdc0353335e7308efc761b..a9936a2c3ed060c475af7823fb154ee8f86be892 100644
--- a/src/liborcus/opc_context.cpp
+++ b/src/liborcus/opc_context.cpp
@@ -240,7 +240,7 @@ opc_relations_context::opc_relations_context(session_context& session_cxt, const
     xml_context_base(session_cxt, _tokens)
 {
     // build content type cache.
-    for (schema_t* p = SCH_all; *p; ++p)
+    for (const schema_t* p = SCH_all; *p; ++p)
         m_schema_cache.insert(std::string_view(*p));
 }
 
diff --git a/src/liborcus/opc_tokens.inl b/src/liborcus/opc_tokens.inl
index 5f72a6a14251c76bdec8bc8a7422200380bf536f..e8cc7c6d8004d1dddd7ff6da11d7210c7ff67cd7 100644
--- a/src/liborcus/opc_tokens.inl
+++ b/src/liborcus/opc_tokens.inl
@@ -1,6 +1,6 @@
 // This file has been auto-generated.  Do not hand-edit this.
 
-const char* token_names[] = {
+const char* const token_names[] = {
     "??", // 0
     "ContentType", // 1
     "Default", // 2
@@ -32,5 +32,5 @@ const char* token_names[] = {
     "version"  // 28
 };
 
-size_t token_name_count = 29;
+const size_t token_name_count = 29;
 
diff --git a/src/liborcus/xls_xml_namespace_types.cpp b/src/liborcus/xls_xml_namespace_types.cpp
index 96ccf6de8041e1acd489058fc4f4bbb9a2104ff6..a93758f9f6fc7630dd9bf523a5075a06a5f774ce 100644
--- a/src/liborcus/xls_xml_namespace_types.cpp
+++ b/src/liborcus/xls_xml_namespace_types.cpp
@@ -16,7 +16,7 @@ const xmlns_id_t NS_xls_xml_html ="http://www.w3.org/TR/REC-html40";
 
 namespace {
 
-xmlns_id_t xls_xml_ns[] = {
+const xmlns_id_t xls_xml_ns[] = {
     NS_xls_xml_ss,
     NS_xls_xml_o,
     NS_xls_xml_x,
@@ -26,7 +26,7 @@ xmlns_id_t xls_xml_ns[] = {
 
 }
 
-const xmlns_id_t* NS_xls_xml_all = xls_xml_ns;
+const xmlns_id_t* const NS_xls_xml_all = xls_xml_ns;
 
 }
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/src/liborcus/xls_xml_namespace_types.hpp b/src/liborcus/xls_xml_namespace_types.hpp
index 37de5b0ab315bd5c60c2ad7057ac3610bc9e739d..de7bf4a1fd64ede7b23b823109d30e4da5038aec 100644
--- a/src/liborcus/xls_xml_namespace_types.hpp
+++ b/src/liborcus/xls_xml_namespace_types.hpp
@@ -20,7 +20,7 @@ extern const xmlns_id_t NS_xls_xml_html;
 /**
  * Null-terminated array of all xls xml namespaces.
  */
-extern const xmlns_id_t* NS_xls_xml_all;
+extern const xmlns_id_t* const NS_xls_xml_all;
 
 }
 
diff --git a/src/liborcus/xls_xml_tokens.inl b/src/liborcus/xls_xml_tokens.inl
index 73cd1fc5a18854ffb0b74db70d7c56b8590abf5e..ca961b9764fe94ac52a8e20f169e29075fc45d08 100644
--- a/src/liborcus/xls_xml_tokens.inl
+++ b/src/liborcus/xls_xml_tokens.inl
@@ -1,6 +1,6 @@
 // This file has been auto-generated.  Do not hand-edit this.
 
-const char* token_names[] = {
+const char* const token_names[] = {
     "??", // 0
     "AcceptLabelsInFormulas", // 1
     "Action", // 2
@@ -994,4 +994,4 @@ const char* token_names[] = {
     "yrange"  // 990
 };
 
-size_t token_name_count = 991;
+const size_t token_name_count = 991;
diff --git a/src/liborcus/yaml_document_tree.cpp b/src/liborcus/yaml_document_tree.cpp
index 1bd37a8bf2b739a2dac199b395aa1f65eba3ad71..c65793f447065ed29bccdfa06095c0ca3c6ed541 100644
--- a/src/liborcus/yaml_document_tree.cpp
+++ b/src/liborcus/yaml_document_tree.cpp
@@ -558,11 +558,11 @@ const_node document_tree::get_document_root(size_t index) const
 
 namespace {
 
-const char* indent = "    ";
-const char* kw_true = "true";
-const char* kw_false = "false";
-const char* kw_tilde = "~";
-const char* kw_null = "null";
+const char* const indent = "    ";
+const char* const kw_true = "true";
+const char* const kw_false = "false";
+const char* const kw_tilde = "~";
+const char* const kw_null = "null";
 
 const char quote = '"';
 
@@ -812,7 +812,7 @@ void dump_json_node(std::ostringstream& os, const yaml_value& node, size_t scope
     }
 }
 
-const char* warning_multiple_documents =
+const char* const warning_multiple_documents =
 "warning: this YAML file contains multiple documents.  Only the first document\n"
 "will be written.";
 
diff --git a/src/parser/tokens.cpp b/src/parser/tokens.cpp
index 5d3c5333df45ce3c7c2c35717039839437b98dce..e28219f78efe3729742b00c1385d9bb195ed7a60 100644
--- a/src/parser/tokens.cpp
+++ b/src/parser/tokens.cpp
@@ -9,7 +9,7 @@
 
 namespace orcus {
 
-tokens::tokens(const char** token_names, size_t token_name_count) :
+tokens::tokens(const char* const* token_names, size_t token_name_count) :
     m_token_names(token_names), 
     m_token_name_count(token_name_count)
 {
diff --git a/src/parser/types.cpp b/src/parser/types.cpp
index ae8843e2f41caecb52b4acddb65def1087b153fb..fdf39cb06e7c4571a4ef926588461d6fe8648f46 100644
--- a/src/parser/types.cpp
+++ b/src/parser/types.cpp
@@ -1427,7 +1427,7 @@ std::ostream& operator<< (std::ostream& os, const date_time_t& v)
 
 std::ostream& operator<< (std::ostream& os, format_t v)
 {
-    static const char* values[] = {
+    static const char* const values[] = {
         "unknown",
         "ods",
         "xlsx",