[glib: 1/2] build: Add glib_debug option

[Philip Withnall <pwithnall src gnome org>]

commit 670b84ca3068eb4ec584812fad2cdcb8dc35683b
Author: Ole André Vadla Ravnås <oleavr gmail com>
Date:   Wed Jan 20 00:37:22 2021 +0100

    build: Add glib_debug option
    
    To allow disabling debug infrastructure in builds with debug symbols.

 docs/macros.txt   | 4 ++++
 meson.build       | 3 ++-
 meson_options.txt | 6 ++++++
 3 files changed, 12 insertions(+), 1 deletion(-)
---
diff --git a/docs/macros.txt b/docs/macros.txt
index aa326a4dc..ec449f17f 100644
--- a/docs/macros.txt
+++ b/docs/macros.txt
@@ -5,6 +5,10 @@ GLib's configure options and corresponding macros
        none
 --buildtype={debug,debugoptimized}     [debugoptimized is the default]
        -DG_ENABLE_DEBUG -g
+-Dglib_debug=disabled
+       Omits G_ENABLE_DEBUG when implied by --buildtype/-Ddebug
+-Dglib_debug=enabled
+       Defines G_ENABLE_DEBUG regardless of --buildtype/-Ddebug
 -Dglib_asserts=false
        -DG_DISABLE_ASSERT
 -Dglib_checks=false
diff --git a/meson.build b/meson.build
index 00c4789e9..f226c4f0f 100644
--- a/meson.build
+++ b/meson.build
@@ -235,7 +235,8 @@ endif
 # Use debug/optimization flags to determine whether to enable debug or disable
 # cast checks
 glib_debug_cflags = []
-if get_option('debug')
+glib_debug = get_option('glib_debug')
+if glib_debug.enabled() or (glib_debug.auto() and get_option('debug'))
   glib_debug_cflags += ['-DG_ENABLE_DEBUG']
   message('Enabling various debug infrastructure')
 elif get_option('optimization') in ['2', '3', 's']
diff --git a/meson_options.txt b/meson_options.txt
index a42136f78..072765361 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -105,6 +105,12 @@ option('oss_fuzz',
        value : 'disabled',
        description : 'Indicate oss-fuzz build environment')
 
+option('glib_debug',
+       type : 'feature',
+       value : 'auto',
+       yield : true,
+       description : 'Enable GLib debug infrastructure (see docs/macros.txt)')
+
 option('glib_assert',
        type : 'boolean',
        value : true,