+feature_check = $(eval $(feature_check_code))
+define feature_check_code
+ feature-$(1) := $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) LDFLAGS=$(LDFLAGS) -C config/feature-checks test-$1 >/dev/null 2>/dev/null && echo 1 || echo 0)
+endef
+
+feature_set = $(eval $(feature_set_code))
+define feature_set_code
+ feature-$(1) := 1
+endef
+
+#
+# Build the feature check binaries in parallel, ignore errors, ignore return value and suppress output:
+#
+
+#
+# Note that this is not a complete list of all feature tests, just
+# those that are typically built on a fully configured system.
+#
+# [ Feature tests not mentioned here have to be built explicitly in
+# the rule that uses them - an example for that is the 'bionic'
+# feature check. ]
+#
+CORE_FEATURE_TESTS = \
+ backtrace \
+ dwarf \
+ fortify-source \
+ glibc \
+ gtk2 \
+ gtk2-infobar \
+ libaudit \
+ libbfd \
+ libelf \
+ libelf-getphdrnum \
+ libelf-mmap \
+ libnuma \
+ libperl \
+ libpython \
+ libpython-version \
+ libslang \
+ libunwind \
+ libunwind-debug-frame \
+ on-exit \
+ stackprotector \
+ stackprotector-all
+
+#
+# So here we detect whether test-all was rebuilt, to be able
+# to skip the print-out of the long features list if the file
+# existed before and after it was built:
+#
+ifeq ($(wildcard $(OUTPUT)config/feature-checks/test-all),)
+ test-all-failed := 1
+else
+ test-all-failed := 0
+endif
+
+#
+# Special fast-path for the 'all features are available' case:
+#
+$(call feature_check,all,$(MSG))
+
+#
+# Just in case the build freshly failed, make sure we print the
+# feature matrix:
+#
+ifeq ($(feature-all), 0)
+ test-all-failed := 1
+endif
+
+ifeq ($(test-all-failed),1)
+ $(info )
+ $(info Auto-detecting system features:)
+endif
+
+ifeq ($(feature-all), 1)
+ #
+ # test-all.c passed - just set all the core feature flags to 1:
+ #
+ $(foreach feat,$(CORE_FEATURE_TESTS),$(call feature_set,$(feat)))
+else
+ $(shell $(MAKE) OUTPUT=$(OUTPUT_FEATURES) LDFLAGS=$(LDFLAGS) -i -j -C config/feature-checks $(CORE_FEATURE_TESTS) >/dev/null 2>&1)
+ $(foreach feat,$(CORE_FEATURE_TESTS),$(call feature_check,$(feat)))
+endif
+
+#
+# Print the result of the feature test:
+#
+feature_print = $(eval $(feature_print_code)) $(info $(MSG))
+
+define feature_print_code
+ ifeq ($(feature-$(1)), 1)
+ MSG = $(shell printf '...%30s: [ \033[32mon\033[m ]' $(1))
+ else
+ MSG = $(shell printf '...%30s: [ \033[31mOFF\033[m ]' $(1))
+ endif
+endef
+
+#
+# Only print out our features if we rebuilt the testcases or if a test failed:
+#
+ifeq ($(test-all-failed), 1)
+ $(foreach feat,$(CORE_FEATURE_TESTS),$(call feature_print,$(feat)))
+ $(info )