From 6cc5978540893f5d33596d9f9f14b34c84529f7e Mon Sep 17 00:00:00 2001
From: David Allsopp <david.allsopp@metastack.com>
Date: Wed, 19 Nov 2025 11:28:02 +0000
Subject: [PATCH] Harden the error handling of shell commands

Run all shell commands from the build system with -e (abort on any
error), -u (abort on undefined variables) and, when available,
-o pipefail (abort if any process in a pipeline exits with non-zero
status)
---
 Makefile         | 2 ++
 doc/Makefile     | 2 ++
 release/Makefile | 2 ++
 src_ext/Makefile | 2 ++
 4 files changed, 8 insertions(+)

diff --git a/Makefile b/Makefile
index d9280b0adfd..4ff375fb597 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,5 @@
+.SHELLFLAGS := -eu$(if $(shell (set -o pipefail 2>/dev/null && echo yes)),o pipefail) $(.SHELLFLAGS)
+
 ifeq ($(filter distclean clean,$(MAKECMDGOALS)),)
 -include Makefile.config
 endif
diff --git a/doc/Makefile b/doc/Makefile
index 5c7d59110f9..30d45e6ca0b 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -1,3 +1,5 @@
+.SHELLFLAGS := -eu$(if $(shell (set -o pipefail 2>/dev/null && echo yes)),o pipefail) $(.SHELLFLAGS)
+
 -include ../Makefile.config
 
 ifeq ($(DUNE),)
diff --git a/release/Makefile b/release/Makefile
index 36e32b3c376..bdd5a2bdceb 100644
--- a/release/Makefile
+++ b/release/Makefile
@@ -1,3 +1,5 @@
+.SHELLFLAGS := -eu$(if $(shell (set -o pipefail 2>/dev/null && echo yes)),o pipefail) $(.SHELLFLAGS)
+
 TAG = master
 VERSION = $(shell git describe $(TAG))
 OPAM_VERSION = $(subst -,~,$(VERSION))
diff --git a/src_ext/Makefile b/src_ext/Makefile
index 0c2fe7b3b67..438f67fa32d 100644
--- a/src_ext/Makefile
+++ b/src_ext/Makefile
@@ -1,3 +1,5 @@
+.SHELLFLAGS := -eu$(if $(shell (set -o pipefail 2>/dev/null && echo yes)),o pipefail) $(.SHELLFLAGS)
+
 ifneq ($(wildcard ../Makefile.config)$(filter-out archives cache-archives,$(MAKECMDGOALS)),)
 -include ../Makefile.config
 endif