Index: meson.build
--- meson.build.orig
+++ meson.build
@@ -12,8 +12,6 @@ project(
 )
 
 add_project_arguments([
-	'-D_POSIX_C_SOURCE=200809L',
-
 	'-Wno-unused-parameter',
 	'-Wno-unused-result',
 	'-Wundef',
