Merge branch 'mcatanzaro/build-best-practices' into 'main'

Improve default value of glib_debug option

See merge request GNOME/glib!2851

docs/reference/glib/building.xml

@@ -205,15 +205,10 @@
       <para>
         This is a standard <application>Meson</application> option which
         specifies how much debugging and optimization to enable. If the build
-        type starts with <literal>debug</literal>,
+        type is <literal>debug</literal>,
         <literal>G_ENABLE_DEBUG</literal> will be defined and GLib will be built
-        with additional debug code enabled.
-      </para>
-      <para>
-        If the build type is <literal>plain</literal>, GLib will not enable any
-        optimization or debug options by default, and will leave it entirely to
-        the user to choose their options. To build with the options recommended
-        by GLib developers, choose <literal>release</literal>.
+        with additional debug code enabled. You can override this behavior using
+        <option>-Dglib_debug</option>.
       </para>
     </formalpara>
 

meson.build

@@ -294,13 +294,15 @@ elif vs_crt_opt == 'from_buildtype'
 endif
 
 # Use debug/optimization flags to determine whether to enable debug or disable
-# cast checks
+# cast checks. We have a non-production (debug) build if debug is true and if
+# optimization is 0 or g; otherwise, we have a production build.
 glib_debug_cflags = []
 glib_debug = get_option('glib_debug')
-if glib_debug.enabled() or (glib_debug.auto() and get_option('debug'))
+optimized_build = get_option('optimization') not in [ '0', 'g' ]
+if glib_debug.enabled() or (glib_debug.auto() and get_option('debug') and not optimized_build)
   glib_debug_cflags += ['-DG_ENABLE_DEBUG']
   message('Enabling various debug infrastructure')
-elif get_option('optimization') in ['2', '3', 's']
+elif optimized_build
   glib_debug_cflags += ['-DG_DISABLE_CAST_CHECKS']
   message('Disabling cast checks')
 endif