diff --git a/source/blender/blenlib/BLI_allocator.h b/source/blender/blenlib/BLI_allocator.hh
similarity index 97%
rename from source/blender/blenlib/BLI_allocator.h
rename to source/blender/blenlib/BLI_allocator.hh
index e2d39c4e897..c52db4aab53 100644
--- a/source/blender/blenlib/BLI_allocator.h
+++ b/source/blender/blenlib/BLI_allocator.hh
@@ -13,8 +13,8 @@
  * along with this program; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
-#ifndef __BLI_ALLOCATOR_H__
-#define __BLI_ALLOCATOR_H__
+#ifndef __BLI_ALLOCATOR_HH__
+#define __BLI_ALLOCATOR_HH__
 
 /** \file
  * \ingroup bli
@@ -102,4 +102,4 @@ class RawAllocator {
 
 }  // namespace BLI
 
-#endif /* __BLI_ALLOCATOR_H__ */
+#endif /* __BLI_ALLOCATOR_HH__ */
diff --git a/source/blender/blenlib/BLI_array_cxx.h b/source/blender/blenlib/BLI_array.hh
similarity index 95%
rename from source/blender/blenlib/BLI_array_cxx.h
rename to source/blender/blenlib/BLI_array.hh
index 8fc2aec6698..c6536f6c1ed 100644
--- a/source/blender/blenlib/BLI_array_cxx.h
+++ b/source/blender/blenlib/BLI_array.hh
@@ -13,8 +13,8 @@
  * along with this program; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
-#ifndef __BLI_ARRAY_CXX_H__
-#define __BLI_ARRAY_CXX_H__
+#ifndef __BLI_ARRAY_HH__
+#define __BLI_ARRAY_HH__
 
 /** \file
  * \ingroup bli
@@ -23,10 +23,10 @@
  * a template argument. Instead it can be specified at the construction time.
  */
 
-#include "BLI_allocator.h"
-#include "BLI_array_ref.h"
-#include "BLI_index_range.h"
-#include "BLI_memory_utils_cxx.h"
+#include "BLI_allocator.hh"
+#include "BLI_array_ref.hh"
+#include "BLI_index_range.hh"
+#include "BLI_memory_utils.hh"
 #include "BLI_utildefines.h"
 
 namespace BLI {
@@ -231,4 +231,4 @@ template<typename T, uint N = 4, typename Allocator = GuardedAllocator> class Ar
 
 }  // namespace BLI
 
-#endif /* __BLI_ARRAY_CXX_H__ */
+#endif /* __BLI_ARRAY_HH__ */
diff --git a/source/blender/blenlib/BLI_array_ref.h b/source/blender/blenlib/BLI_array_ref.hh
similarity index 98%
rename from source/blender/blenlib/BLI_array_ref.h
rename to source/blender/blenlib/BLI_array_ref.hh
index 2c2e441a47d..dd9421d289c 100644
--- a/source/blender/blenlib/BLI_array_ref.h
+++ b/source/blender/blenlib/BLI_array_ref.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_ARRAY_REF_H__
-#define __BLI_ARRAY_REF_H__
+#ifndef __BLI_ARRAY_REF_HH__
+#define __BLI_ARRAY_REF_HH__
 
 /** \file
  * \ingroup bli
@@ -41,8 +41,8 @@
 #include <string>
 #include <vector>
 
-#include "BLI_index_range.h"
-#include "BLI_memory_utils_cxx.h"
+#include "BLI_index_range.hh"
+#include "BLI_memory_utils.hh"
 #include "BLI_utildefines.h"
 
 namespace BLI {
@@ -542,4 +542,4 @@ void assert_same_size(const T1 &v1, const T2 &v2, const T3 &v3)
 
 } /* namespace BLI */
 
-#endif /* __BLI_ARRAY_REF_H__ */
+#endif /* __BLI_ARRAY_REF_HH__ */
diff --git a/source/blender/blenlib/BLI_hash_cxx.h b/source/blender/blenlib/BLI_hash.hh
similarity index 97%
rename from source/blender/blenlib/BLI_hash_cxx.h
rename to source/blender/blenlib/BLI_hash.hh
index 22941a792ba..b5041012189 100644
--- a/source/blender/blenlib/BLI_hash_cxx.h
+++ b/source/blender/blenlib/BLI_hash.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_HASH_CXX_H__
-#define __BLI_HASH_CXX_H__
+#ifndef __BLI_HASH_HH__
+#define __BLI_HASH_HH__
 
 /** \file
  * \ingroup bli
@@ -109,4 +109,4 @@ template<typename T1, typename T2> struct DefaultHash<std::pair<T1, T2>> {
 
 }  // namespace BLI
 
-#endif /* __BLI_HASH_CXX_H__ */
+#endif /* __BLI_HASH_HH__ */
diff --git a/source/blender/blenlib/BLI_index_range.h b/source/blender/blenlib/BLI_index_range.hh
similarity index 97%
rename from source/blender/blenlib/BLI_index_range.h
rename to source/blender/blenlib/BLI_index_range.hh
index 4553c996454..e24fd567810 100644
--- a/source/blender/blenlib/BLI_index_range.h
+++ b/source/blender/blenlib/BLI_index_range.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_INDEX_RANGE_H__
-#define __BLI_INDEX_RANGE_H__
+#ifndef __BLI_INDEX_RANGE_HH__
+#define __BLI_INDEX_RANGE_HH__
 
 /** \file
  * \ingroup bli
@@ -208,4 +208,4 @@ class IndexRange {
 
 }  // namespace BLI
 
-#endif /* __BLI_INDEX_RANGE_H__ */
+#endif /* __BLI_INDEX_RANGE_HH__ */
diff --git a/source/blender/blenlib/BLI_listbase_wrapper.h b/source/blender/blenlib/BLI_listbase_wrapper.hh
similarity index 95%
rename from source/blender/blenlib/BLI_listbase_wrapper.h
rename to source/blender/blenlib/BLI_listbase_wrapper.hh
index d6832166e35..0eee00c87b9 100644
--- a/source/blender/blenlib/BLI_listbase_wrapper.h
+++ b/source/blender/blenlib/BLI_listbase_wrapper.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_LISTBASE_WRAPPER_H__
-#define __BLI_LISTBASE_WRAPPER_H__
+#ifndef __BLI_LISTBASE_WRAPPER_HH__
+#define __BLI_LISTBASE_WRAPPER_HH__
 
 /** \file
  * \ingroup bli
@@ -110,4 +110,4 @@ template<typename T> class IntrusiveListBaseWrapper {
 
 } /* namespace BLI */
 
-#endif /* __BLI_LISTBASE_WRAPPER_H__ */
+#endif /* __BLI_LISTBASE_WRAPPER_HH__ */
diff --git a/source/blender/blenlib/BLI_map.h b/source/blender/blenlib/BLI_map.hh
similarity index 99%
rename from source/blender/blenlib/BLI_map.h
rename to source/blender/blenlib/BLI_map.hh
index 4b7ac0791d9..626c971c959 100644
--- a/source/blender/blenlib/BLI_map.h
+++ b/source/blender/blenlib/BLI_map.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_MAP_H__
-#define __BLI_MAP_H__
+#ifndef __BLI_MAP_HH__
+#define __BLI_MAP_HH__
 
 /** \file
  * \ingroup bli
@@ -26,9 +26,9 @@
  * lookups. Keys and values are stored in groups of four to avoid wasting memory due to padding.
  */
 
-#include "BLI_array_ref.h"
-#include "BLI_hash_cxx.h"
-#include "BLI_open_addressing.h"
+#include "BLI_array_ref.hh"
+#include "BLI_hash.hh"
+#include "BLI_open_addressing.hh"
 
 namespace BLI {
 
@@ -733,4 +733,4 @@ template<typename KeyT, typename ValueT, typename Allocator = GuardedAllocator>
 
 }  // namespace BLI
 
-#endif /* __BLI_MAP_H__ */
+#endif /* __BLI_MAP_HH__ */
diff --git a/source/blender/blenlib/BLI_memory_utils_cxx.h b/source/blender/blenlib/BLI_memory_utils.hh
similarity index 96%
rename from source/blender/blenlib/BLI_memory_utils_cxx.h
rename to source/blender/blenlib/BLI_memory_utils.hh
index 6534138315d..d9acf08a43f 100644
--- a/source/blender/blenlib/BLI_memory_utils_cxx.h
+++ b/source/blender/blenlib/BLI_memory_utils.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_MEMORY_UTILS_CXX_H__
-#define __BLI_MEMORY_UTILS_CXX_H__
+#ifndef __BLI_MEMORY_UTILS_HH__
+#define __BLI_MEMORY_UTILS_HH__
 
 /** \file
  * \ingroup bli
@@ -120,4 +120,4 @@ template<uint Size, uint Alignment> class alignas(Alignment) AlignedBuffer {
 
 }  // namespace BLI
 
-#endif /* __BLI_MEMORY_UTILS_CXX_H__ */
+#endif /* __BLI_MEMORY_UTILS_HH__ */
diff --git a/source/blender/blenlib/BLI_open_addressing.h b/source/blender/blenlib/BLI_open_addressing.hh
similarity index 97%
rename from source/blender/blenlib/BLI_open_addressing.h
rename to source/blender/blenlib/BLI_open_addressing.hh
index 6a0acd418eb..fa2ea6d8f94 100644
--- a/source/blender/blenlib/BLI_open_addressing.h
+++ b/source/blender/blenlib/BLI_open_addressing.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_OPEN_ADDRESSING_H__
-#define __BLI_OPEN_ADDRESSING_H__
+#ifndef __BLI_OPEN_ADDRESSING_HH__
+#define __BLI_OPEN_ADDRESSING_HH__
 
 /** \file
  * \ingroup bli
@@ -33,9 +33,9 @@
 
 #include <cmath>
 
-#include "BLI_allocator.h"
+#include "BLI_allocator.hh"
 #include "BLI_math_base.h"
-#include "BLI_memory_utils_cxx.h"
+#include "BLI_memory_utils.hh"
 #include "BLI_utildefines.h"
 
 namespace BLI {
@@ -302,4 +302,4 @@ class OpenAddressingArray {
 
 }  // namespace BLI
 
-#endif /* __BLI_OPEN_ADDRESSING_H__ */
+#endif /* __BLI_OPEN_ADDRESSING_HH__ */
diff --git a/source/blender/blenlib/BLI_optional.h b/source/blender/blenlib/BLI_optional.hh
similarity index 96%
rename from source/blender/blenlib/BLI_optional.h
rename to source/blender/blenlib/BLI_optional.hh
index 267c858e0f2..eac11293781 100644
--- a/source/blender/blenlib/BLI_optional.h
+++ b/source/blender/blenlib/BLI_optional.hh
@@ -20,10 +20,10 @@
  * Simple version of std::optional, which is only available since C++17.
  */
 
-#ifndef __BLI_OPTIONAL_H__
-#define __BLI_OPTIONAL_H__
+#ifndef __BLI_OPTIONAL_HH__
+#define __BLI_OPTIONAL_HH__
 
-#include "BLI_memory_utils_cxx.h"
+#include "BLI_memory_utils.hh"
 #include "BLI_utildefines.h"
 
 #include <algorithm>
@@ -196,4 +196,4 @@ template<typename T> class Optional {
 
 } /* namespace BLI */
 
-#endif /* __BLI_OPTIONAL_H__ */
+#endif /* __BLI_OPTIONAL_HH__ */
diff --git a/source/blender/blenlib/BLI_set.h b/source/blender/blenlib/BLI_set.hh
similarity index 98%
rename from source/blender/blenlib/BLI_set.h
rename to source/blender/blenlib/BLI_set.hh
index dc101add1a7..2ef92bf1c48 100644
--- a/source/blender/blenlib/BLI_set.h
+++ b/source/blender/blenlib/BLI_set.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_SET_H__
-#define __BLI_SET_H__
+#ifndef __BLI_SET_HH__
+#define __BLI_SET_HH__
 
 /** \file
  * \ingroup bli
@@ -23,9 +23,9 @@
  * This file provides a set implementation that uses open addressing with probing.
  */
 
-#include "BLI_hash_cxx.h"
-#include "BLI_open_addressing.h"
-#include "BLI_vector.h"
+#include "BLI_hash.hh"
+#include "BLI_open_addressing.hh"
+#include "BLI_vector.hh"
 
 namespace BLI {
 
@@ -480,4 +480,4 @@ template<typename T, typename Allocator = GuardedAllocator> class Set {
 
 }  // namespace BLI
 
-#endif /* __BLI_SET_H__ */
+#endif /* __BLI_SET_HH__ */
diff --git a/source/blender/blenlib/BLI_stack_cxx.h b/source/blender/blenlib/BLI_stack.hh
similarity index 96%
rename from source/blender/blenlib/BLI_stack_cxx.h
rename to source/blender/blenlib/BLI_stack.hh
index a26318a3dcb..a0e8cec3b6f 100644
--- a/source/blender/blenlib/BLI_stack_cxx.h
+++ b/source/blender/blenlib/BLI_stack.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_STACK_CXX_H__
-#define __BLI_STACK_CXX_H__
+#ifndef __BLI_STACK_HH__
+#define __BLI_STACK_HH__
 
 /** \file
  * \ingroup bli
@@ -23,7 +23,7 @@
  * Basic stack implementation with support for small object optimization.
  */
 
-#include "BLI_vector.h"
+#include "BLI_vector.hh"
 
 namespace BLI {
 
@@ -147,4 +147,4 @@ template<typename T, uint N = 4, typename Allocator = GuardedAllocator> class St
 
 } /* namespace BLI */
 
-#endif /* __BLI_STACK_CXX_H__ */
+#endif /* __BLI_STACK_HH__ */
diff --git a/source/blender/blenlib/BLI_string_map.h b/source/blender/blenlib/BLI_string_map.hh
similarity index 98%
rename from source/blender/blenlib/BLI_string_map.h
rename to source/blender/blenlib/BLI_string_map.hh
index f304b140bcc..d47f57c8bcc 100644
--- a/source/blender/blenlib/BLI_string_map.h
+++ b/source/blender/blenlib/BLI_string_map.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_STRING_MAP_H__
-#define __BLI_STRING_MAP_H__
+#ifndef __BLI_STRING_MAP_HH__
+#define __BLI_STRING_MAP_HH__
 
 /** \file
  * \ingroup bli
@@ -27,10 +27,10 @@
  * make it more efficient later on. Also, even if we will never implement this optimization, having
  * a special map with string keys can be quite handy. */
 
-#include "BLI_map.h"
-#include "BLI_optional.h"
-#include "BLI_string_ref.h"
-#include "BLI_vector.h"
+#include "BLI_map.hh"
+#include "BLI_optional.hh"
+#include "BLI_string_ref.hh"
+#include "BLI_vector.hh"
 
 namespace BLI {
 
@@ -457,4 +457,4 @@ template<typename T, typename Allocator = GuardedAllocator> class StringMap {
 
 }  // namespace BLI
 
-#endif /* __BLI_STRING_MAP_H__ */
+#endif /* __BLI_STRING_MAP_HH__ */
diff --git a/source/blender/blenlib/BLI_string_ref.h b/source/blender/blenlib/BLI_string_ref.hh
similarity index 97%
rename from source/blender/blenlib/BLI_string_ref.h
rename to source/blender/blenlib/BLI_string_ref.hh
index 2389542bcea..6c750a81e06 100644
--- a/source/blender/blenlib/BLI_string_ref.h
+++ b/source/blender/blenlib/BLI_string_ref.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_STRING_REF_H__
-#define __BLI_STRING_REF_H__
+#ifndef __BLI_STRING_REF_HH__
+#define __BLI_STRING_REF_HH__
 
 /** \file
  * \ingroup bli
@@ -32,7 +32,7 @@
 #include <sstream>
 #include <string>
 
-#include "BLI_array_ref.h"
+#include "BLI_array_ref.hh"
 #include "BLI_utildefines.h"
 
 namespace BLI {
@@ -252,4 +252,4 @@ inline StringRef StringRefBase::substr(uint start, uint size) const
 
 }  // namespace BLI
 
-#endif /* __BLI_STRING_REF_H__ */
+#endif /* __BLI_STRING_REF_HH__ */
diff --git a/source/blender/blenlib/BLI_utility_mixins.h b/source/blender/blenlib/BLI_utility_mixins.hh
similarity index 93%
rename from source/blender/blenlib/BLI_utility_mixins.h
rename to source/blender/blenlib/BLI_utility_mixins.hh
index ce7a4ce094a..441575f9111 100644
--- a/source/blender/blenlib/BLI_utility_mixins.h
+++ b/source/blender/blenlib/BLI_utility_mixins.hh
@@ -18,8 +18,8 @@
  * \ingroup bli
  */
 
-#ifndef __BLI_UTILITY_MIXINS_H__
-#define __BLI_UTILITY_MIXINS_H__
+#ifndef __BLI_UTILITY_MIXINS_HH__
+#define __BLI_UTILITY_MIXINS_HH__
 
 namespace BLI {
 
@@ -49,4 +49,4 @@ class NonMovable {
 
 }  // namespace BLI
 
-#endif /* __BLI_UTILITY_MIXINS_H__ */
+#endif /* __BLI_UTILITY_MIXINS_HH__ */
diff --git a/source/blender/blenlib/BLI_vector.h b/source/blender/blenlib/BLI_vector.hh
similarity index 98%
rename from source/blender/blenlib/BLI_vector.h
rename to source/blender/blenlib/BLI_vector.hh
index 6a708759d0e..31e046f82e8 100644
--- a/source/blender/blenlib/BLI_vector.h
+++ b/source/blender/blenlib/BLI_vector.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_VECTOR_H__
-#define __BLI_VECTOR_H__
+#ifndef __BLI_VECTOR_HH__
+#define __BLI_VECTOR_HH__
 
 /** \file
  * \ingroup bli
@@ -31,12 +31,12 @@
 #include <iostream>
 #include <memory>
 
-#include "BLI_allocator.h"
-#include "BLI_array_ref.h"
-#include "BLI_index_range.h"
-#include "BLI_listbase_wrapper.h"
+#include "BLI_allocator.hh"
+#include "BLI_array_ref.hh"
+#include "BLI_index_range.hh"
+#include "BLI_listbase_wrapper.hh"
 #include "BLI_math_base.h"
-#include "BLI_memory_utils_cxx.h"
+#include "BLI_memory_utils.hh"
 #include "BLI_utildefines.h"
 
 #include "MEM_guardedalloc.h"
@@ -665,4 +665,4 @@ template<typename T, uint N = 20> using ScopedVector = Vector<T, N, GuardedAlloc
 
 } /* namespace BLI */
 
-#endif /* __BLI_VECTOR_H__ */
+#endif /* __BLI_VECTOR_HH__ */
diff --git a/source/blender/blenlib/BLI_vector_set.h b/source/blender/blenlib/BLI_vector_set.hh
similarity index 98%
rename from source/blender/blenlib/BLI_vector_set.h
rename to source/blender/blenlib/BLI_vector_set.hh
index 99d955c60d8..c3cecfc0acf 100644
--- a/source/blender/blenlib/BLI_vector_set.h
+++ b/source/blender/blenlib/BLI_vector_set.hh
@@ -14,8 +14,8 @@
  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
-#ifndef __BLI_VECTOR_SET_H__
-#define __BLI_VECTOR_SET_H__
+#ifndef __BLI_VECTOR_SET_HH__
+#define __BLI_VECTOR_SET_HH__
 
 /** \file
  * \ingroup bli
@@ -25,9 +25,9 @@
  * no deletes. The expected time to check if a value is in the VectorSet is O(1).
  */
 
-#include "BLI_hash_cxx.h"
-#include "BLI_open_addressing.h"
-#include "BLI_vector.h"
+#include "BLI_hash.hh"
+#include "BLI_open_addressing.hh"
+#include "BLI_vector.hh"
 
 namespace BLI {
 
@@ -422,4 +422,4 @@ template<typename T, typename Allocator = GuardedAllocator> class VectorSet {
 
 }  // namespace BLI
 
-#endif /* __BLI_VECTOR_SET_H__ */
+#endif /* __BLI_VECTOR_SET_HH__ */
diff --git a/source/blender/blenlib/CMakeLists.txt b/source/blender/blenlib/CMakeLists.txt
index 6cc0532828e..0835f09fa5d 100644
--- a/source/blender/blenlib/CMakeLists.txt
+++ b/source/blender/blenlib/CMakeLists.txt
@@ -136,11 +136,11 @@ set(SRC
 
 
   BLI_alloca.h
-  BLI_allocator.h
+  BLI_allocator.hh
   BLI_args.h
   BLI_array.h
-  BLI_array_cxx.h
-  BLI_array_ref.h
+  BLI_array.hh
+  BLI_array_ref.hh
   BLI_array_store.h
   BLI_array_store_utils.h
   BLI_array_utils.h
@@ -176,13 +176,13 @@ set(SRC
   BLI_ghash.h
   BLI_gsqueue.h
   BLI_hash.h
-  BLI_hash_cxx.h
+  BLI_hash.hh
   BLI_hash_md5.h
   BLI_hash_mm2a.h
   BLI_hash_mm3.h
   BLI_heap.h
   BLI_heap_simple.h
-  BLI_index_range.h
+  BLI_index_range.hh
   BLI_iterator.h
   BLI_jitter_2d.h
   BLI_kdopbvh.h
@@ -194,8 +194,8 @@ set(SRC
   BLI_linklist_lockfree.h
   BLI_linklist_stack.h
   BLI_listbase.h
-  BLI_listbase_wrapper.h
-  BLI_map.h
+  BLI_listbase_wrapper.hh
+  BLI_map.hh
   BLI_math.h
   BLI_math_base.h
   BLI_math_bits.h
@@ -213,11 +213,11 @@ set(SRC
   BLI_memblock.h
   BLI_memiter.h
   BLI_memory_utils.h
-  BLI_memory_utils_cxx.h
+  BLI_memory_utils.hh
   BLI_mempool.h
   BLI_noise.h
-  BLI_open_addressing.h
-  BLI_optional.h
+  BLI_open_addressing.hh
+  BLI_optional.hh
   BLI_path_util.h
   BLI_polyfill_2d.h
   BLI_polyfill_2d_beautify.h
@@ -225,17 +225,17 @@ set(SRC
   BLI_rand.h
   BLI_rect.h
   BLI_scanfill.h
-  BLI_set.h
+  BLI_set.hh
   BLI_smallhash.h
   BLI_sort.h
   BLI_sort_utils.h
   BLI_stack.h
-  BLI_stack_cxx.h
+  BLI_stack.hh
   BLI_strict_flags.h
   BLI_string.h
   BLI_string_cursor_utf8.h
-  BLI_string_map.h
-  BLI_string_ref.h
+  BLI_string_map.hh
+  BLI_string_ref.hh
   BLI_string_utf8.h
   BLI_string_utils.h
   BLI_sys_types.h
@@ -248,10 +248,10 @@ set(SRC
   BLI_utildefines_iter.h
   BLI_utildefines_stack.h
   BLI_utildefines_variadic.h
-  BLI_utility_mixins.h
+  BLI_utility_mixins.hh
   BLI_uvproject.h
-  BLI_vector.h
-  BLI_vector_set.h
+  BLI_vector.hh
+  BLI_vector_set.hh
   BLI_vfontdata.h
   BLI_voronoi_2d.h
   BLI_voxel.h
diff --git a/source/blender/blenlib/intern/BLI_index_range.cc b/source/blender/blenlib/intern/BLI_index_range.cc
index 90eb4e4a89c..fefb6e6598e 100644
--- a/source/blender/blenlib/intern/BLI_index_range.cc
+++ b/source/blender/blenlib/intern/BLI_index_range.cc
@@ -17,10 +17,10 @@
 #include <atomic>
 #include <mutex>
 
-#include "BLI_array_cxx.h"
-#include "BLI_array_ref.h"
-#include "BLI_index_range.h"
-#include "BLI_vector.h"
+#include "BLI_array.hh"
+#include "BLI_array_ref.hh"
+#include "BLI_index_range.hh"
+#include "BLI_vector.hh"
 
 namespace BLI {
 
diff --git a/source/blender/modifiers/intern/MOD_mask.cc b/source/blender/modifiers/intern/MOD_mask.cc
index 3bdb5a3fd54..31370ddf04e 100644
--- a/source/blender/modifiers/intern/MOD_mask.cc
+++ b/source/blender/modifiers/intern/MOD_mask.cc
@@ -46,9 +46,9 @@
 
 #include "MOD_modifiertypes.h"
 
-#include "BLI_array_cxx.h"
-#include "BLI_listbase_wrapper.h"
-#include "BLI_vector.h"
+#include "BLI_array.hh"
+#include "BLI_listbase_wrapper.hh"
+#include "BLI_vector.hh"
 
 using BLI::Array;
 using BLI::ArrayRef;
diff --git a/tests/gtests/blenlib/BLI_array_ref_test.cc b/tests/gtests/blenlib/BLI_array_ref_test.cc
index aacd6113161..7a1f54e7458 100644
--- a/tests/gtests/blenlib/BLI_array_ref_test.cc
+++ b/tests/gtests/blenlib/BLI_array_ref_test.cc
@@ -1,5 +1,5 @@
-#include "BLI_array_ref.h"
-#include "BLI_vector.h"
+#include "BLI_array_ref.hh"
+#include "BLI_vector.hh"
 #include "testing/testing.h"
 
 using namespace BLI;
diff --git a/tests/gtests/blenlib/BLI_array_test.cc b/tests/gtests/blenlib/BLI_array_test.cc
index dd09c2d20f8..b1aa24aa808 100644
--- a/tests/gtests/blenlib/BLI_array_test.cc
+++ b/tests/gtests/blenlib/BLI_array_test.cc
@@ -1,4 +1,4 @@
-#include "BLI_array_cxx.h"
+#include "BLI_array.hh"
 #include "testing/testing.h"
 
 using namespace BLI;
diff --git a/tests/gtests/blenlib/BLI_index_range_test.cc b/tests/gtests/blenlib/BLI_index_range_test.cc
index 60da18b6baf..b12502f0d97 100644
--- a/tests/gtests/blenlib/BLI_index_range_test.cc
+++ b/tests/gtests/blenlib/BLI_index_range_test.cc
@@ -1,5 +1,5 @@
-#include "BLI_index_range.h"
-#include "BLI_vector.h"
+#include "BLI_index_range.hh"
+#include "BLI_vector.hh"
 #include "testing/testing.h"
 
 using BLI::ArrayRef;
diff --git a/tests/gtests/blenlib/BLI_map_test.cc b/tests/gtests/blenlib/BLI_map_test.cc
index 7be23157e94..2d052635c88 100644
--- a/tests/gtests/blenlib/BLI_map_test.cc
+++ b/tests/gtests/blenlib/BLI_map_test.cc
@@ -1,5 +1,5 @@
-#include "BLI_map.h"
-#include "BLI_set.h"
+#include "BLI_map.hh"
+#include "BLI_set.hh"
 #include "testing/testing.h"
 
 using BLI::Map;
diff --git a/tests/gtests/blenlib/BLI_optional_test.cc b/tests/gtests/blenlib/BLI_optional_test.cc
index a25a3cbd588..e0dec5681fe 100644
--- a/tests/gtests/blenlib/BLI_optional_test.cc
+++ b/tests/gtests/blenlib/BLI_optional_test.cc
@@ -1,4 +1,4 @@
-#include "BLI_optional.h"
+#include "BLI_optional.hh"
 #include "testing/testing.h"
 #include <string>
 
diff --git a/tests/gtests/blenlib/BLI_set_test.cc b/tests/gtests/blenlib/BLI_set_test.cc
index 555140f805c..2bb0b26dd20 100644
--- a/tests/gtests/blenlib/BLI_set_test.cc
+++ b/tests/gtests/blenlib/BLI_set_test.cc
@@ -1,5 +1,5 @@
-#include "BLI_set.h"
-#include "BLI_vector.h"
+#include "BLI_set.hh"
+#include "BLI_vector.hh"
 #include "testing/testing.h"
 
 using BLI::Set;
diff --git a/tests/gtests/blenlib/BLI_stack_cxx_test.cc b/tests/gtests/blenlib/BLI_stack_cxx_test.cc
index 6376259927b..e49872f8643 100644
--- a/tests/gtests/blenlib/BLI_stack_cxx_test.cc
+++ b/tests/gtests/blenlib/BLI_stack_cxx_test.cc
@@ -1,4 +1,4 @@
-#include "BLI_stack_cxx.h"
+#include "BLI_stack.hh"
 #include "testing/testing.h"
 
 using BLI::Stack;
diff --git a/tests/gtests/blenlib/BLI_string_map_test.cc b/tests/gtests/blenlib/BLI_string_map_test.cc
index 4cb67d5fbac..5e671da86c7 100644
--- a/tests/gtests/blenlib/BLI_string_map_test.cc
+++ b/tests/gtests/blenlib/BLI_string_map_test.cc
@@ -1,5 +1,5 @@
-#include "BLI_string_map.h"
-#include "BLI_vector.h"
+#include "BLI_string_map.hh"
+#include "BLI_vector.hh"
 #include "testing/testing.h"
 
 using namespace BLI;
diff --git a/tests/gtests/blenlib/BLI_string_ref_test.cc b/tests/gtests/blenlib/BLI_string_ref_test.cc
index a268bf3215a..1c0b641bbb5 100644
--- a/tests/gtests/blenlib/BLI_string_ref_test.cc
+++ b/tests/gtests/blenlib/BLI_string_ref_test.cc
@@ -1,5 +1,5 @@
-#include "BLI_string_ref.h"
-#include "BLI_vector.h"
+#include "BLI_string_ref.hh"
+#include "BLI_vector.hh"
 #include "testing/testing.h"
 
 using BLI::StringRef;
diff --git a/tests/gtests/blenlib/BLI_vector_set_test.cc b/tests/gtests/blenlib/BLI_vector_set_test.cc
index 5ec51337aa7..410e7a1b319 100644
--- a/tests/gtests/blenlib/BLI_vector_set_test.cc
+++ b/tests/gtests/blenlib/BLI_vector_set_test.cc
@@ -1,4 +1,4 @@
-#include "BLI_vector_set.h"
+#include "BLI_vector_set.hh"
 #include "testing/testing.h"
 
 using BLI::VectorSet;
diff --git a/tests/gtests/blenlib/BLI_vector_test.cc b/tests/gtests/blenlib/BLI_vector_test.cc
index 2402ee9627f..09f007f5eda 100644
--- a/tests/gtests/blenlib/BLI_vector_test.cc
+++ b/tests/gtests/blenlib/BLI_vector_test.cc
@@ -1,4 +1,4 @@
-#include "BLI_vector.h"
+#include "BLI_vector.hh"
 #include "testing/testing.h"
 #include <forward_list>