Cleanup: take includes out of 'extern "C"' blocks

Surrounding includes with an 'extern "C"' block is not necessary anymore.
Also that made it harder to add any C++ code to some headers, or include headers
that have "optional" C++ code like `MEM_guardedalloc.h`.

I tested compilation on linux and windows (and got help from @LazyDodo).
If this still breaks compilation due to some linker error, the header containing
the symbol in question is probably missing an 'extern "C"' block.

Differential Revision: https://developer.blender.org/D7653

24 files changed, 1 insertions, 48 deletions

diff --git a/source/blender/io/alembic/intern/abc_customdata.cc b/source/blender/io/alembic/intern/abc_customdata.cc
index c5f60ac3e29..64f8f9c81a8 100644
--- a/source/blender/io/alembic/intern/abc_customdata.cc
+++ b/source/blender/io/alembic/intern/abc_customdata.cc
@@ -27,7 +27,6 @@
 #include <algorithm>
 #include <unordered_map>
 
-extern "C" {
 #include "DNA_customdata_types.h"
 #include "DNA_meshdata_types.h"
 
@@ -35,7 +34,6 @@ extern "C" {
 #include "BLI_utildefines.h"
 
 #include "BKE_customdata.h"
-}
 
 /* NOTE: for now only UVs and Vertex Colors are supported for streaming.
  * Although Alembic only allows for a single UV layer per {I|O}Schema, and does
diff --git a/source/blender/io/alembic/intern/abc_exporter.cc b/source/blender/io/alembic/intern/abc_exporter.cc
index f661083b0a7..dbf24452b78 100644
--- a/source/blender/io/alembic/intern/abc_exporter.cc
+++ b/source/blender/io/alembic/intern/abc_exporter.cc
@@ -33,7 +33,6 @@
 #include "abc_writer_points.h"
 #include "abc_writer_transform.h"
 
-extern "C" {
 #include "DNA_camera_types.h"
 #include "DNA_curve_types.h"
 #include "DNA_fluid_types.h"
@@ -62,7 +61,6 @@ extern "C" {
 #include "BKE_scene.h"
 
 #include "DEG_depsgraph_query.h"
-}
 
 using Alembic::Abc::OBox3dProperty;
 using Alembic::Abc::TimeSamplingPtr;
diff --git a/source/blender/io/alembic/intern/abc_reader_archive.cc b/source/blender/io/alembic/intern/abc_reader_archive.cc
index 6ad44553701..ea8478f7b56 100644
--- a/source/blender/io/alembic/intern/abc_reader_archive.cc
+++ b/source/blender/io/alembic/intern/abc_reader_archive.cc
@@ -23,12 +23,10 @@
 
 #include "abc_reader_archive.h"
 
-extern "C" {
 #include "BKE_main.h"
 
 #include "BLI_path_util.h"
 #include "BLI_string.h"
-}
 
 #ifdef WIN32
 #  include "utfconv.h"
diff --git a/source/blender/io/alembic/intern/abc_reader_camera.cc b/source/blender/io/alembic/intern/abc_reader_camera.cc
index ab506f32cbe..0752534f8c2 100644
--- a/source/blender/io/alembic/intern/abc_reader_camera.cc
+++ b/source/blender/io/alembic/intern/abc_reader_camera.cc
@@ -22,7 +22,6 @@
 #include "abc_reader_transform.h"
 #include "abc_util.h"
 
-extern "C" {
 #include "DNA_camera_types.h"
 #include "DNA_object_types.h"
 
@@ -30,7 +29,6 @@ extern "C" {
 #include "BKE_object.h"
 
 #include "BLI_math.h"
-}
 
 using Alembic::AbcGeom::CameraSample;
 using Alembic::AbcGeom::ICamera;
diff --git a/source/blender/io/alembic/intern/abc_reader_curves.cc b/source/blender/io/alembic/intern/abc_reader_curves.cc
index 9fdc8b2b93f..1fda102a3cd 100644
--- a/source/blender/io/alembic/intern/abc_reader_curves.cc
+++ b/source/blender/io/alembic/intern/abc_reader_curves.cc
@@ -30,7 +30,6 @@
 
 #include "MEM_guardedalloc.h"
 
-extern "C" {
 #include "DNA_curve_types.h"
 #include "DNA_object_types.h"
 
@@ -39,7 +38,6 @@ extern "C" {
 #include "BKE_curve.h"
 #include "BKE_mesh.h"
 #include "BKE_object.h"
-}
 
 using Alembic::Abc::FloatArraySamplePtr;
 using Alembic::Abc::Int32ArraySamplePtr;
diff --git a/source/blender/io/alembic/intern/abc_reader_mesh.cc b/source/blender/io/alembic/intern/abc_reader_mesh.cc
index a5c893a262a..f22f2a53a78 100644
--- a/source/blender/io/alembic/intern/abc_reader_mesh.cc
+++ b/source/blender/io/alembic/intern/abc_reader_mesh.cc
@@ -27,7 +27,6 @@
 
 #include "MEM_guardedalloc.h"
 
-extern "C" {
 #include "DNA_material_types.h"
 #include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
@@ -40,7 +39,6 @@ extern "C" {
 #include "BKE_mesh.h"
 #include "BKE_modifier.h"
 #include "BKE_object.h"
-}
 
 using Alembic::Abc::Int32ArraySamplePtr;
 using Alembic::Abc::P3fArraySamplePtr;
diff --git a/source/blender/io/alembic/intern/abc_reader_nurbs.cc b/source/blender/io/alembic/intern/abc_reader_nurbs.cc
index a57a1f55608..10d9a35a8e1 100644
--- a/source/blender/io/alembic/intern/abc_reader_nurbs.cc
+++ b/source/blender/io/alembic/intern/abc_reader_nurbs.cc
@@ -25,7 +25,6 @@
 
 #include "MEM_guardedalloc.h"
 
-extern "C" {
 #include "DNA_curve_types.h"
 #include "DNA_object_types.h"
 
@@ -34,7 +33,6 @@ extern "C" {
 
 #include "BKE_curve.h"
 #include "BKE_object.h"
-}
 
 using Alembic::AbcGeom::FloatArraySamplePtr;
 using Alembic::AbcGeom::kWrapExisting;
diff --git a/source/blender/io/alembic/intern/abc_reader_object.cc b/source/blender/io/alembic/intern/abc_reader_object.cc
index c40421da8c2..e5bd0771a42 100644
--- a/source/blender/io/alembic/intern/abc_reader_object.cc
+++ b/source/blender/io/alembic/intern/abc_reader_object.cc
@@ -22,7 +22,6 @@
 #include "abc_axis_conversion.h"
 #include "abc_util.h"
 
-extern "C" {
 #include "DNA_cachefile_types.h"
 #include "DNA_constraint_types.h"
 #include "DNA_modifier_types.h"
@@ -37,7 +36,6 @@ extern "C" {
 #include "BLI_math_geom.h"
 #include "BLI_string.h"
 #include "BLI_utildefines.h"
-}
 
 using Alembic::AbcGeom::IObject;
 using Alembic::AbcGeom::IXform;
diff --git a/source/blender/io/alembic/intern/abc_reader_object.h b/source/blender/io/alembic/intern/abc_reader_object.h
index 94923df2df9..dcc2697e0b5 100644
--- a/source/blender/io/alembic/intern/abc_reader_object.h
+++ b/source/blender/io/alembic/intern/abc_reader_object.h
@@ -24,9 +24,7 @@
 #include <Alembic/Abc/All.h>
 #include <Alembic/AbcGeom/All.h>
 
-extern "C" {
 #include "DNA_ID.h"
-}
 
 struct CacheFile;
 struct Main;
diff --git a/source/blender/io/alembic/intern/abc_reader_points.cc b/source/blender/io/alembic/intern/abc_reader_points.cc
index e4dc345f868..2b82dadbcbc 100644
--- a/source/blender/io/alembic/intern/abc_reader_points.cc
+++ b/source/blender/io/alembic/intern/abc_reader_points.cc
@@ -26,14 +26,12 @@
 #include "abc_reader_transform.h"
 #include "abc_util.h"
 
-extern "C" {
 #include "DNA_mesh_types.h"
 #include "DNA_object_types.h"
 
 #include "BKE_customdata.h"
 #include "BKE_mesh.h"
 #include "BKE_object.h"
-}
 
 using Alembic::AbcGeom::kWrapExisting;
 using Alembic::AbcGeom::N3fArraySamplePtr;
diff --git a/source/blender/io/alembic/intern/abc_reader_transform.cc b/source/blender/io/alembic/intern/abc_reader_transform.cc
index ce569a9ccb5..3df391f8432 100644
--- a/source/blender/io/alembic/intern/abc_reader_transform.cc
+++ b/source/blender/io/alembic/intern/abc_reader_transform.cc
@@ -21,13 +21,11 @@
 #include "abc_reader_transform.h"
 #include "abc_util.h"
 
-extern "C" {
 #include "DNA_object_types.h"
 
 #include "BLI_utildefines.h"
 
 #include "BKE_object.h"
-}
 
 using Alembic::Abc::ISampleSelector;
 
diff --git a/source/blender/io/alembic/intern/abc_util.cc b/source/blender/io/alembic/intern/abc_util.cc
index 6b27c389363..1f3bd2a1aaa 100644
--- a/source/blender/io/alembic/intern/abc_util.cc
+++ b/source/blender/io/alembic/intern/abc_util.cc
@@ -32,13 +32,11 @@
 
 #include <algorithm>
 
-extern "C" {
 #include "DNA_object_types.h"
 
 #include "BLI_math_geom.h"
 
 #include "PIL_time.h"
-}
 
 std::string get_id_name(const Object *const ob)
 {
diff --git a/source/blender/io/alembic/intern/abc_writer_archive.cc b/source/blender/io/alembic/intern/abc_writer_archive.cc
index af18d480a18..ea0d684347d 100644
--- a/source/blender/io/alembic/intern/abc_writer_archive.cc
+++ b/source/blender/io/alembic/intern/abc_writer_archive.cc
@@ -22,14 +22,13 @@
  */
 
 #include "abc_writer_archive.h"
-extern "C" {
+
 #include "BKE_blender_version.h"
 
 #include "BLI_path_util.h"
 #include "BLI_string.h"
 
 #include "DNA_scene_types.h"
-}
 
 #ifdef WIN32
 #  include "utfconv.h"
diff --git a/source/blender/io/alembic/intern/abc_writer_camera.cc b/source/blender/io/alembic/intern/abc_writer_camera.cc
index e705e5ba911..07ae81e584f 100644
--- a/source/blender/io/alembic/intern/abc_writer_camera.cc
+++ b/source/blender/io/alembic/intern/abc_writer_camera.cc
@@ -21,10 +21,8 @@
 #include "abc_writer_camera.h"
 #include "abc_writer_transform.h"
 
-extern "C" {
 #include "DNA_camera_types.h"
 #include "DNA_object_types.h"
-}
 
 using Alembic::AbcGeom::OCamera;
 using Alembic::AbcGeom::OFloatProperty;
diff --git a/source/blender/io/alembic/intern/abc_writer_curves.cc b/source/blender/io/alembic/intern/abc_writer_curves.cc
index 8cb40c4ffab..0deda76e123 100644
--- a/source/blender/io/alembic/intern/abc_writer_curves.cc
+++ b/source/blender/io/alembic/intern/abc_writer_curves.cc
@@ -26,14 +26,12 @@
 #include "abc_reader_curves.h"
 #include "abc_writer_transform.h"
 
-extern "C" {
 #include "DNA_curve_types.h"
 #include "DNA_object_types.h"
 
 #include "BKE_curve.h"
 #include "BKE_mesh.h"
 #include "BKE_object.h"
-}
 
 using Alembic::AbcGeom::OCompoundProperty;
 using Alembic::AbcGeom::OCurves;
diff --git a/source/blender/io/alembic/intern/abc_writer_hair.cc b/source/blender/io/alembic/intern/abc_writer_hair.cc
index dd1203de835..ed62889b03d 100644
--- a/source/blender/io/alembic/intern/abc_writer_hair.cc
+++ b/source/blender/io/alembic/intern/abc_writer_hair.cc
@@ -24,7 +24,6 @@
 
 #include <cstdio>
 
-extern "C" {
 #include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
 #include "DNA_modifier_types.h"
@@ -35,7 +34,6 @@ extern "C" {
 #include "BKE_mesh.h"
 #include "BKE_mesh_runtime.h"
 #include "BKE_particle.h"
-}
 
 using Alembic::Abc::P3fArraySamplePtr;
 
diff --git a/source/blender/io/alembic/intern/abc_writer_mball.cc b/source/blender/io/alembic/intern/abc_writer_mball.cc
index 151848674f9..3593acf18b0 100644
--- a/source/blender/io/alembic/intern/abc_writer_mball.cc
+++ b/source/blender/io/alembic/intern/abc_writer_mball.cc
@@ -21,7 +21,6 @@
 #include "abc_writer_mball.h"
 #include "abc_writer_mesh.h"
 
-extern "C" {
 #include "DNA_mesh_types.h"
 #include "DNA_meta_types.h"
 #include "DNA_object_types.h"
@@ -33,7 +32,6 @@ extern "C" {
 #include "BKE_object.h"
 
 #include "BLI_utildefines.h"
-}
 
 AbcMBallWriter::AbcMBallWriter(Main *bmain,
                                Object *ob,
diff --git a/source/blender/io/alembic/intern/abc_writer_mesh.cc b/source/blender/io/alembic/intern/abc_writer_mesh.cc
index 38939d15c85..d5ab4e34828 100644
--- a/source/blender/io/alembic/intern/abc_writer_mesh.cc
+++ b/source/blender/io/alembic/intern/abc_writer_mesh.cc
@@ -22,7 +22,6 @@
 #include "abc_axis_conversion.h"
 #include "abc_writer_transform.h"
 
-extern "C" {
 #include "DNA_material_types.h"
 #include "DNA_mesh_types.h"
 #include "DNA_meshdata_types.h"
@@ -40,7 +39,6 @@ extern "C" {
 #include "bmesh_tools.h"
 
 #include "DEG_depsgraph_query.h"
-}
 
 using Alembic::Abc::FloatArraySample;
 using Alembic::Abc::Int32ArraySample;
diff --git a/source/blender/io/alembic/intern/abc_writer_nurbs.cc b/source/blender/io/alembic/intern/abc_writer_nurbs.cc
index 3521c62075f..8b4a1050d33 100644
--- a/source/blender/io/alembic/intern/abc_writer_nurbs.cc
+++ b/source/blender/io/alembic/intern/abc_writer_nurbs.cc
@@ -22,14 +22,12 @@
 #include "abc_axis_conversion.h"
 #include "abc_writer_transform.h"
 
-extern "C" {
 #include "DNA_curve_types.h"
 #include "DNA_object_types.h"
 
 #include "BLI_listbase.h"
 
 #include "BKE_curve.h"
-}
 
 using Alembic::AbcGeom::FloatArraySample;
 using Alembic::AbcGeom::OBoolProperty;
diff --git a/source/blender/io/alembic/intern/abc_writer_object.cc b/source/blender/io/alembic/intern/abc_writer_object.cc
index 75dc93bd08e..f4a3587f54d 100644
--- a/source/blender/io/alembic/intern/abc_writer_object.cc
+++ b/source/blender/io/alembic/intern/abc_writer_object.cc
@@ -20,11 +20,9 @@
 
 #include "abc_writer_object.h"
 
-extern "C" {
 #include "DNA_object_types.h"
 
 #include "BKE_object.h"
-}
 
 AbcObjectWriter::AbcObjectWriter(Object *ob,
                                  uint32_t time_sampling,
diff --git a/source/blender/io/alembic/intern/abc_writer_object.h b/source/blender/io/alembic/intern/abc_writer_object.h
index c3511566372..830c4aee903 100644
--- a/source/blender/io/alembic/intern/abc_writer_object.h
+++ b/source/blender/io/alembic/intern/abc_writer_object.h
@@ -26,9 +26,7 @@
 
 #include "abc_exporter.h"
 
-extern "C" {
 #include "DNA_ID.h"
-}
 
 class AbcTransformWriter;
 
diff --git a/source/blender/io/alembic/intern/abc_writer_points.cc b/source/blender/io/alembic/intern/abc_writer_points.cc
index 70a1ead239a..7b5cf47431c 100644
--- a/source/blender/io/alembic/intern/abc_writer_points.cc
+++ b/source/blender/io/alembic/intern/abc_writer_points.cc
@@ -26,7 +26,6 @@
 #include "abc_writer_mesh.h"
 #include "abc_writer_transform.h"
 
-extern "C" {
 #include "DNA_object_types.h"
 #include "DNA_particle_types.h"
 
@@ -36,7 +35,6 @@ extern "C" {
 #include "BLI_math.h"
 
 #include "DEG_depsgraph_query.h"
-}
 
 using Alembic::AbcGeom::kVertexScope;
 using Alembic::AbcGeom::OPoints;
diff --git a/source/blender/io/alembic/intern/abc_writer_transform.cc b/source/blender/io/alembic/intern/abc_writer_transform.cc
index 18f4487cf05..1ec7db0a1c6 100644
--- a/source/blender/io/alembic/intern/abc_writer_transform.cc
+++ b/source/blender/io/alembic/intern/abc_writer_transform.cc
@@ -23,13 +23,11 @@
 
 #include <OpenEXR/ImathBoxAlgo.h>
 
-extern "C" {
 #include "DNA_object_types.h"
 
 #include "BLI_math.h"
 
 #include "DEG_depsgraph_query.h"
-}
 
 using Alembic::AbcGeom::OObject;
 using Alembic::AbcGeom::OXform;
diff --git a/source/blender/io/alembic/intern/alembic_capi.cc b/source/blender/io/alembic/intern/alembic_capi.cc
index ced5791e0e8..987a3cacb3b 100644
--- a/source/blender/io/alembic/intern/alembic_capi.cc
+++ b/source/blender/io/alembic/intern/alembic_capi.cc
@@ -40,7 +40,6 @@
 
 #include "MEM_guardedalloc.h"
 
-extern "C" {
 #include "DNA_cachefile_types.h"
 #include "DNA_curve_types.h"
 #include "DNA_modifier_types.h"
@@ -74,7 +73,6 @@ extern "C" {
 
 #include "WM_api.h"
 #include "WM_types.h"
-}
 
 using Alembic::Abc::Int32ArraySamplePtr;
 using Alembic::Abc::ObjectHeader;