Refactor: Build generated DNA files as C++

Pull Request: https://projects.blender.org/blender/blender/pulls/134469

source/blender/makesdna/DNA_genfile.h

@@ -13,10 +13,6 @@
 
 struct SDNA;
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
 /**
  * DNAstr contains the prebuilt SDNA structure defining the layouts of the types
  * used by this version of Blender. It is defined in a file dna.c, which is
@@ -254,7 +250,3 @@ void DNA_sdna_alias_data_ensure_structs_map(struct SDNA *sdna);
 #  define DNA_struct_member_exists(sdna, stype, vartype, name) \
     DNA_struct_member_exists_with_alias(sdna, stype, vartype, name)
 #endif
-
-#ifdef __cplusplus
-}
-#endif

source/blender/makesdna/intern/CMakeLists.txt

@@ -98,18 +98,18 @@ if(WIN32 AND NOT UNIX)
   endif()
 endif()
 
-# Output dna.c
+# Output dna.cc
 add_custom_command(
   OUTPUT
-    ${CMAKE_CURRENT_BINARY_DIR}/dna.c
+    ${CMAKE_CURRENT_BINARY_DIR}/dna.cc
     ${CMAKE_CURRENT_BINARY_DIR}/dna_type_offsets.h
-    ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.c
+    ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.cc
   COMMAND
     ${CMAKE_COMMAND} -E env ${PLATFORM_ENV_BUILD}
     "$<TARGET_FILE:makesdna>"
-    ${CMAKE_CURRENT_BINARY_DIR}/dna.c
+    ${CMAKE_CURRENT_BINARY_DIR}/dna.cc
     ${CMAKE_CURRENT_BINARY_DIR}/dna_type_offsets.h
-    ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.c
+    ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.cc
     ${CMAKE_SOURCE_DIR}/source/blender/makesdna/
   DEPENDS makesdna
 )
@@ -121,8 +121,8 @@ set(SRC
   dna_defaults.c
   dna_genfile.cc
   dna_utils.cc
-  ${CMAKE_CURRENT_BINARY_DIR}/dna.c
-  ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.c
+  ${CMAKE_CURRENT_BINARY_DIR}/dna.cc
+  ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.cc
   ${SRC_DNA_INC}
 
   ${CMAKE_CURRENT_BINARY_DIR}/dna_type_offsets.h
@@ -131,9 +131,9 @@ set(SRC
 )
 
 set_source_files_properties(
-  ${CMAKE_CURRENT_BINARY_DIR}/dna.c
+  ${CMAKE_CURRENT_BINARY_DIR}/dna.cc
   ${CMAKE_CURRENT_BINARY_DIR}/dna_type_offsets.h
-  ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.c
+  ${CMAKE_CURRENT_BINARY_DIR}/dna_verify.cc
   PROPERTIES GENERATED TRUE
 )