Merge branch '1919-relative-paths' into 'master'

build: Rework path construction to reliably add prefix

Closes #1919

See merge request GNOME/glib!1369

gio/gdbus-2.0/codegen/meson.build

@@ -24,7 +24,7 @@ gdbus_codegen = configure_file(input : 'gdbus-codegen.in',
   # Provide tools for others when we're a subproject and they use the Meson GNOME module
 meson.override_find_program('gdbus-codegen', gdbus_codegen)
 
-codegen_dir = join_paths(get_option('datadir'), 'glib-2.0/codegen')
+codegen_dir = join_paths(glib_datadir, 'glib-2.0', 'codegen')
 
 gdbus_codegen_built_files = []
 gdbus_codegen_built_files += configure_file(input : 'config.py.in',

gio/meson.build

@@ -805,9 +805,10 @@ libgio = library('gio-2.0',
   link_args : [noseh_link_args, glib_link_flags],
 )
 
-giomodulesdir = get_option('gio_module_dir')
-if giomodulesdir == ''
-  giomodulesdir = join_paths('${libdir}', 'gio', 'modules')
+if get_option('gio_module_dir') != ''
+  pkgconfig_giomodulesdir = join_paths('${prefix}', get_option('gio_module_dir'))
+else
+  pkgconfig_giomodulesdir = join_paths('${libdir}', 'gio', 'modules')
 endif
 
 schemas_subdir = join_paths('glib-2.0', 'schemas')
@@ -818,7 +819,7 @@ pkg.generate(libgio,
   variables : ['datadir=' + join_paths('${prefix}', get_option('datadir')),
                'schemasdir=' + join_paths('${datadir}', schemas_subdir),
                'bindir=' + join_paths('${prefix}', get_option('bindir')),
-               'giomoduledir=' + giomodulesdir,
+               'giomoduledir=' + pkgconfig_giomodulesdir,
                'gio=' + join_paths('${bindir}', 'gio'),
                'gio_querymodules=' + join_paths('${bindir}', 'gio-querymodules'),
                'glib_compile_schemas=' + join_paths('${bindir}', 'glib-compile-schemas'),