[PATCH v2 2/3] Makefile: add a utility to dump variables

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Nov 1, 2021, 19:19 UTC
Message-ID: <patch-v2-2.3-97738b056cf-20211101T191231Z-avarab@gmail.com>
In-Reply-To: <cover-v2-0.3-00000000000-20211101T191231Z-avarab@gmail.com>

Add handy "print-var-%" and "print-list-%" targets, these can both be used for ad-hoc debugging, and to integrate the Makefile into some other build system which needs to extract information from it.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Makefile | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Makefile b/Makefile
index 100658dfa43..4139bcf675c 100644
--- a/Makefile
+++ b/Makefile
@@ -590,6 +590,14 @@ TEST_OBJS =
 TEST_PROGRAMS_NEED_X =
 THIRD_PARTY_SOURCES =
 
+# Utility to dump whatever variables are defined here
+print-var-%:
+	@echo $($*)
+
+print-list-%:
+	@echo $* =
+	@for v in $($*); do echo $* += $$v; done
+
 # Having this variable in your environment would break pipelines because
 # you cause "cd" to echo its destination to stdout.  It can also take
 # scripts to unexpected places.  If you like CDPATH, define it for your

-- 
2.33.1.1570.g069344fdd45