From 5f7647dc0cdb8cbdacdb5e817ebb3131a58faba0 Mon Sep 17 00:00:00 2001
From: Christopher Haster <geky@geky.net>
Date: Mon, 21 Apr 2025 15:09:19 -0500
Subject: [PATCH] make: Forward all LFS_* prefixed environment variables as
 defines

So instead of:

  CFLAGS='-DLFS_YES_REVDBG=1' make

You can just do:

  LFS_YES_REVDBG=1 make

I've been hesitant to add this, as I've never seen this pattern in
another project (why?), but it's just too convenient to not give it a
try.
---
 Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile b/Makefile
index 5f8f2a85..fdf64a69 100644
--- a/Makefile
+++ b/Makefile
@@ -95,6 +95,9 @@ ifdef PERFBDGEN
 CFLAGS += -fno-omit-frame-pointer
 endif
 
+# also forward all LFS_* environment variables
+CFLAGS += $(foreach D,$(filter LFS_%,$(.VARIABLES)),-D$D=$($D))
+
 TEST_CFLAGS += -Wno-unused-function
 TEST_CFLAGS += -Wno-format-overflow