From 7a3320f4bb4af5a6d1844fdefb7f2d3178917ccf Mon Sep 17 00:00:00 2001
From: Ross Patterson <me@rpatterson.net>
Date: Thu, 17 Sep 2020 11:54:49 -0700
Subject: [PATCH] build(make): Defensive make settings

https://tech.davis-hansson.com/p/make/

Prevents things like silent shell pipeline errors in recipes, unexpected behavior from
undefined variables, etc.
---
 Makefile | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Makefile b/Makefile
index 6dd87409e..e85f29b48 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,16 @@
 
 # NOTE: this Makefile requires GNU make
 
+### Defensive settings for make:
+#     https://tech.davis-hansson.com/p/make/
+SHELL := bash
+.ONESHELL:
+.SHELLFLAGS := -xeu -o pipefail -c
+.SILENT:
+.DELETE_ON_ERROR:
+MAKEFLAGS += --warn-undefined-variables
+MAKEFLAGS += --no-builtin-rules
+
 default:
 	@echo "no default target"