[gtk/fix.vs2013.link.4-2] gtk/meson.build: Fix linking on Visual Studio 2013

[Chun-wei Fan <fanchunwei src gnome org>]

commit b7cf6fc05827e8d730341647fb4e8f67192a2985
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Sat May 22 22:11:05 2021 +0800

    gtk/meson.build: Fix linking on Visual Studio 2013
    
    Visual Studio 2013's linker does not suport `/WHOLEARCHIVE:`, so
    `link_whole:` needs to be updated in order to fix this.  In the
    meanwhile, just explicitly extract the objects from the static libraries
    that will form the final GTK DLL.

 gtk/meson.build | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)
---
diff --git a/gtk/meson.build b/gtk/meson.build
index fe0ec456d9..29cbef084f 100644
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -1116,11 +1116,31 @@ libgtk_static = static_library('gtk',
   link_with: [libgtk_css, libgdk, libgsk ],
 )
 
+# `link_whole:` is actually only supported on Visual Studio 2015 Update 2
+# or later via the linker flag `/WHOLEARCHIVE:<static_lib>`, so we need
+# to work around it for Visual Studio 2013.  Note that all needed static
+# libs are required so that we grab the object files from each of them to
+# link the final GTK DLL.
+if cc.get_id() == 'msvc' and cc.version().split('.').get(0) < '19'
+  whole_archives = []
+
+  # Add libgdk_broadway when ported later, if opted
+  gtk4_objs = [ libgtk_static.extract_all_objects(),
+                libgtk_css.extract_all_objects(),
+                libgdk.extract_all_objects(),
+                libgdk_win32.extract_all_objects(),
+                libgsk.extract_all_objects()]
+else
+  whole_archives = [libgtk_static, libgtk_css, libgdk, libgsk ]
+  gtk4_objs = []
+endif
+
 libgtk = shared_library('gtk-4',
   c_args: gtk_cargs + common_cflags,
   include_directories: [confinc, gdkinc, gskinc, gtkinc],
   dependencies: gtk_deps + [libgtk_css_dep, libgdk_dep, libgsk_dep],
-  link_whole: [libgtk_static, libgtk_css, libgdk, libgsk ],
+  link_whole: whole_archives,
+  objects: gtk4_objs,
   link_args: common_ldflags,
   soversion: gtk_soversion,
   version: gtk_library_version,