gtk: Speed up build

Avoid serializing the gresource blob into a C string
and running gcc over it. Instead, use ld to put it
directly into an .o file and add it to the build.

The build system machinations here were copied from
gobject/tests/meson.build, and should ideally be part
of the meson gnome module.

diff --git a/gtk/meson.build b/gtk/meson.build
index bc097fdd6fc565b91b8b84d9c8617bfc606f508c..8907c1c6dd93fe89da3b2cb1b90b7e4f3119a4d2 100644 (file)
--- a/gtk/meson.build
+++ b/gtk/meson.build
@@ -863,17 +863,80 @@ if not fs.exists('theme/Default/Default-light.css')
   endif
 endif
 
-gtkresources = gnome.compile_resources('gtkresources',
-  gtk_gresources_xml,
-  dependencies: theme_deps,
-  source_dir: [
-    # List in order of preference
-    meson.current_build_dir(),
-    meson.current_source_dir(),
-  ],
-  c_name: '_gtk',
-  extra_args: '--manual-register',
-)
+
+objcopy_supports_add_symbol = false
+objcopy = find_program('objcopy', required : false)
+if objcopy.found()
+  objcopy_supports_add_symbol = run_command(objcopy, '--help').stdout().contains('--add-symbol')
+endif
+
+ld = find_program('ld', required : false)
+
+if build_machine.system() == 'linux' and objcopy.found() and objcopy_supports_add_symbol and ld.found()
+  glib_compile_resources = find_program('glib-compile-resources')
+
+  # Create the resource blob
+  gtk_gresource = custom_target('gtk.gresource',
+      input : gtk_gresources_xml,
+      depends : theme_deps,
+      output : 'gtk.gresource',
+      command : [glib_compile_resources,
+                 '--target=@OUTPUT@',
+                 '--sourcedir=' + meson.current_source_dir(),
+                 '--sourcedir=' + meson.current_build_dir(),
+                 '@INPUT@'])
+
+  # Create resource data file
+  gtk_resources_c = custom_target('gtk_resources.c',
+      input : gtk_gresources_xml,
+      depends : theme_deps,
+      output : 'gtk_resources.c',
+      command : [glib_compile_resources,
+                 '--target=@OUTPUT@',
+                 '--sourcedir=' + meson.current_source_dir(),
+                 '--sourcedir=' + meson.current_build_dir(),
+                 '--generate-source',
+                 '--external-data',
+                 '--c-name', '_gtk',
+                 '--manual-register',
+                 '@INPUT@'])
+
+  # Create object file containing resource data
+  gtk_resources_binary = custom_target('gtk_resources.o',
+      input : gtk_gresource,
+      output : 'gtk_resources.o',
+      command : [ld,
+                 '-r',
+                 '-b','binary',
+                 '@INPUT@',
+                 '-o','@OUTPUT@'])
+
+  # Rename symbol to match the one in the C file
+  gtk_resources_o = custom_target('gtk_resources2.o',
+    input : gtk_resources_binary,
+    output : 'gtk_resources2.o',
+    command : [objcopy,
+                 '--add-symbol','_gtk_resource_data=.data:0',
+                 '@INPUT@',
+                 '@OUTPUT@'])
+
+  gtkresources = [
+      gtk_resources_c,
+      gtk_resources_o,
+    ]
+else
+  gtkresources = gnome.compile_resources('gtkresources',
+    gtk_gresources_xml,
+    dependencies: theme_deps,
+    source_dir: [
+      # List in order of preference
+      meson.current_build_dir(),
+      meson.current_source_dir(),
+    ],
+    c_name: '_gtk',
+    extra_args: '--manual-register',
+  )
+endif
 
 foreach lang : [ 'de', 'fr', 'es', 'zh' ]
   conf = configuration_data()