From edbbe115a268529e7a9c095c12508d0355567aac Mon Sep 17 00:00:00 2001
From: Noah Thornton <noah_thornton@apple.com>
Date: Thu, 20 Aug 2026 16:29:10 -0700
Subject: [PATCH] Add a SWIFT_CONFIGURATION_EXTRA hook for extra swift build
 flags

SWIFT_CONFIGURATION is a := assignment carrying -warnings-as-errors and
-enable-testing, so a caller wanting to add a flag had to override the whole
variable and thereby drop those. Append an overridable
SWIFT_CONFIGURATION_EXTRA instead, so extra flags compose with the existing
configuration rather than replacing it.

Empty by default, so this is a no-op unless set.
---
 Makefile | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index e8c353c86..70bbbc11e 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,10 @@
 # Version and build configuration variables
 BUILD_CONFIGURATION ?= debug
 WARNINGS_AS_ERRORS ?= true
-SWIFT_CONFIGURATION := $(if $(filter-out false,$(WARNINGS_AS_ERRORS)),-Xswiftc -warnings-as-errors) -Xswiftc -enable-testing
+# Extra swift build flags, appended last so callers can add to (rather than
+# replace) the configuration above.
+SWIFT_CONFIGURATION_EXTRA ?=
+SWIFT_CONFIGURATION := $(if $(filter-out false,$(WARNINGS_AS_ERRORS)),-Xswiftc -warnings-as-errors) -Xswiftc -enable-testing $(SWIFT_CONFIGURATION_EXTRA)
 # Code-coverage instrumentation, layered onto the shared build stages. Empty for
 # ordinary builds; the coverage-* targets opt in via a target-specific value so
 # only those goals compile instrumented binaries.