Add explicit version flags for macOS builds

Autotools automatically adds version related linker flags on macOS that
are not related to the version information. Since we want to maintain
binary compatibility, we should do the same when building on macOS.

Fixes: #108

src/meson.build

@@ -51,10 +51,14 @@ foreach h: headers
   epoxy_headers += join_paths(meson.source_root(), 'include/epoxy/@0@'.format(h))
 endforeach
 
+common_ldflags = []
 if cc.get_id() == 'gcc'
   common_ldflags = [ '-Wl,-Bsymbolic', '-Wl,-z,relro', '-Wl,-z,now', ]
-else
-  common_ldflags = []
+endif
+
+# Maintain compatibility with autotools; see: https://github.com/anholt/libepoxy/issues/108
+if host_system == 'darwin'
+  common_ldflags += [ '-compatibility_version=1', '-current_version=1.0', ]
 endif
 
 epoxy_deps = [ dl_dep, ]