glib: fix installing gdb scripts

the disk space cost is less than 20Kb

They provide pretty printers for datascructures likes hash tables in
gdb.

To check that the scripts are loaded:
run gdb on any glib application (for example gio from the bin output)
run info auto-load python-scripts
observe scripts whose filename is libglib-...-gdb.py

pkgs/development/libraries/glib/default.nix

@@ -111,6 +111,12 @@ stdenv.mkDerivation (finalAttrs: {
     # 3. Tools for desktop environment that cannot go to $bin due to $out depending on them ($out)
     #    * gio-launch-desktop
     ./split-dev-programs.patch
+
+    # Tell Meson to install gdb scripts next to the lib
+    # GDB only looks there and in ${gdb}/share/gdb/auto-load,
+    # and by default meson installs in to $out/share/gdb/auto-load
+    # which does not help
+    ./gdb_script.patch
   ];
 
   outputs = [ "bin" "out" "dev" "devdoc" ];
@@ -208,6 +214,7 @@ stdenv.mkDerivation (finalAttrs: {
 
   postInstall = ''
     moveToOutput "share/glib-2.0" "$dev"
+    moveToOutput "share/glib-2.0/gdb" "$out"
     substituteInPlace "$dev/bin/gdbus-codegen" --replace "$out" "$dev"
     sed -i "$dev/bin/glib-gettextize" -e "s|^gettext_dir=.*|gettext_dir=$dev/share/glib-2.0/gettext|"
 

pkgs/development/libraries/glib/gdb_script.patch

@@ -0,0 +1,23 @@
+diff --git a/glib/meson.build b/glib/meson.build
+index b2dd569e1..b013991a1 100644
+--- a/glib/meson.build
++++ b/glib/meson.build
+@@ -541,7 +540,7 @@ configure_file(
+   input: 'libglib-gdb.py.in',
+   output: 'libglib-2.0.so.@0@-gdb.py'.format(library_version),
+   configuration: gdb_conf,
+-  install_dir: gdb_install_dir,
++  install_dir: glib_libdir,
+   install_tag: 'devel',
+   install: gdb_install,
+ )
+diff --git a/gobject/meson.build b/gobject/meson.build
+@@ -185,7 +184,7 @@ configure_file(
+   input: 'libgobject-gdb.py.in',
+   output: 'libgobject-2.0.so.@0@-gdb.py'.format(library_version),
+   configuration: gdb_conf,
+-  install_dir: gdb_install_dir,
++  install_dir: glib_libdir,
+   install_tag: 'devel',
+   install: gdb_install,
+ )