From 02d579d7571a25947a46f0c1d149dc0d90269e17 Mon Sep 17 00:00:00 2001
From: Dorota Czaplejewicz <dorota.czaplejewicz@puri.sm>
Date: Mon, 21 Sep 2020 10:02:22 +0000
Subject: [PATCH] build: Enable unused warnings in C

The goal is to be free of unused X class of problems. For this, CI and any "serious" builds will fail on warnings. Debug builds, used in development, will warn by default but not fail.

In addition, the 'strict' build option is added for when the debug build should fail on unused warnings as well.
---
 meson.build       | 12 +++++++++++-
 meson_options.txt |  4 ++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/meson.build b/meson.build
index d8e0e1bb..80b85f81 100644
--- a/meson.build
+++ b/meson.build
@@ -26,7 +26,7 @@ add_project_arguments(
     '-Wold-style-definition',
     '-Wredundant-decls',
     '-Wstrict-prototypes',
-    '-Wunused-function',
+    '-Wunused',
   ],
   language: 'c'
 )
@@ -38,6 +38,16 @@ conf_data = configuration_data()
 if get_option('buildtype').startswith('debug')
     add_project_arguments('-DDEBUG=1', language : 'c')
 endif
+
+if get_option('strict')
+    add_project_arguments(
+        [
+            '-Werror=unused',
+        ],
+        language: 'c'
+    )
+endif
+
 if get_option('buildtype') != 'plain'
     add_project_arguments('-fstack-protector-strong', language: 'c')
 endif
diff --git a/meson_options.txt b/meson_options.txt
index 180f12f3..bb68374d 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -10,3 +10,7 @@ option('tests',
 option('legacy',
        type: 'boolean', value: false,
        description: 'Build with Deban Buster versions of dependencies')
+
+option('strict',
+       type: 'boolean', value: true,
+       description: 'Turn more warnings into errors')