build: Move feature test macros to prelude.h

This replaces the explicit CPPFLAGS list in flags.mk with just
`-include src/prelude.h`, shortening our compiler command lines and
allowing them to be easily documented.

1 files changed, 0 insertions, 1 deletions

diff --git a/src/dir.c b/src/dir.c
index 0a93fe0..4bf72a1 100644
--- a/src/dir.c
+++ b/src/dir.c
@@ -1,7 +1,6 @@
 // Copyright © Tavian Barnes <tavianator@tavianator.com>
 // SPDX-License-Identifier: 0BSD
 
-#include "prelude.h"
 #include "dir.h"
 
 #include "alloc.h"