Skip to content

Makefile: track environment variable changes #1260

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Nov 3, 2025
Merged

Makefile: track environment variable changes #1260

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 17 additions & 1 deletion test/mk/config.mk
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -78,9 +78,17 @@ endif
# Include retained variables #
##############################

RETAINED_VARS := CROSS_PREFIX CYCLES OPT AUTO

# Capture values of environment variables before setting defaults,
# this ensures we can detect when they change in order to trigger a rebuild.
define CAPTURE_VAR
$(1)_FROM_ENV := $$($(1))
endef
$(foreach var,$(RETAINED_VARS),$(eval $(call CAPTURE_VAR,$(var))))

CYCLES ?=
OPT ?= 1
RETAINED_VARS := CROSS_PREFIX CYCLES OPT AUTO

BUILD_DIR ?= test/build

Expand All @@ -91,6 +99,14 @@ CONFIG := $(BUILD_DIR)/config.mk

-include $(CONFIG)

# After including the cached config, restore environment/command-line values if they were set
define RESTORE_VAR
ifneq ($$($(1)_FROM_ENV),)
$(1) := $$($(1)_FROM_ENV)
endif
endef
$(foreach var,$(RETAINED_VARS),$(eval $(call RESTORE_VAR,$(var))))

$(CONFIG):
@echo " GEN $@"
$(Q)[ -d $(@D) ] || mkdir -p $(@D)
Expand Down
Loading