[gnome-desktop/mcatanzaro/version-script] Add a linker version script

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 291123101a7fda85a7ee36891274f214b3a48e01
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Thu Feb 21 00:03:21 2019 -0600

    Add a linker version script
    
    Life without -export-symbols-regex, the only useful libtool feature :(
    
    I checked with abidiff to ensure this actually worked.
    
    Fixes #103

 libgnome-desktop/meson.build | 7 +++++++
 libgnome-desktop/symbol.map  | 6 ++++++
 2 files changed, 13 insertions(+)
---
diff --git a/libgnome-desktop/meson.build b/libgnome-desktop/meson.build
index c365b448..8503215f 100644
--- a/libgnome-desktop/meson.build
+++ b/libgnome-desktop/meson.build
@@ -82,12 +82,19 @@ gnome_desktop_deps = [
   seccomp_dep
 ]
 
+ldflags = []
+symbol_map = '-Wl,--version-script=@0@'.format(meson.current_source_dir() / 'symbol.map')
+if cc.has_link_argument(symbol_map)
+  ldflags += symbol_map
+endif
+
 libgnome_desktop = library('gnome-desktop-3',
   libgnome_desktop_sources,
   dependencies: [gnome_desktop_deps, m_dep, rt_dep, x_dep],
   soversion: soversion,
   version: libversion,
   c_args: libargs,
+  link_args: ldflags,
   install: true
 )
 
diff --git a/libgnome-desktop/symbol.map b/libgnome-desktop/symbol.map
new file mode 100644
index 00000000..671c1560
--- /dev/null
+++ b/libgnome-desktop/symbol.map
@@ -0,0 +1,6 @@
+{
+global:
+  gnome_*;
+local:
+  *;
+};