[build] Share multi-app code

build/helpers.mk

@@ -34,3 +34,22 @@ endef
 define object_for
 $(call direct_object_for,$(call any_variant,$(1)))
 endef
+
+# Multi-arch helpers
+ifdef ARCHS
+ifndef ARCH
+
+# This rule allow us to build any executable (%) for a specified ARCH ($1)
+# We depend on a phony target to make sure this rule is always executed
+.PHONY: force_remake
+define rule_for_arch_executable
+.PRECIOUS: $$(BUILD_DIR)/$(1)/%.$$(EXE)
+$$(BUILD_DIR)/$(1)/%.$$(EXE): force_remake
+	$(Q) echo "MAKE    ARCH=$(1)"
+	$(Q) $$(MAKE) ARCH=$(1) --silent $$*.$$(EXE)
+endef
+
+$(foreach ARCH,$(ARCHS),$(eval $(call rule_for_arch_executable,$(ARCH))))
+
+endif
+endif

build/platform.simulator.android.mak

@@ -1,10 +1,12 @@
 TOOLCHAIN = android
+EXE = so
 
 EPSILON_TELEMETRY ?= 1
 
 ARCHS = armeabi-v7a arm64-v8a x86 x86_64
 
 ifdef ARCH
-EXE = so
 BUILD_DIR := $(BUILD_DIR)/$(ARCH)
+else
+HANDY_TARGETS_EXTENSIONS = apk
 endif

build/platform.simulator.ios.mak

@@ -1,4 +1,5 @@
 TOOLCHAIN = apple
+EXE = bin
 
 APPLE_PLATFORM ?= ios
 APPLE_PLATFORM_MIN_VERSION = 8.0
@@ -14,8 +15,7 @@ endif
 BUILD_DIR := $(subst $(TARGET),$(APPLE_PLATFORM),$(BUILD_DIR))
 
 ifdef ARCH
-EXE = bin
 BUILD_DIR := $(BUILD_DIR)/$(ARCH)
 else
-HANDY_TARGETS_EXTENSIONS = ipa
+HANDY_TARGETS_EXTENSIONS = ipa app
 endif

build/platform.simulator.macos.mak

@@ -1,4 +1,5 @@
 TOOLCHAIN = apple
+EXE = bin
 
 APPLE_PLATFORM = macos
 APPLE_PLATFORM_MIN_VERSION = 10.10
@@ -8,7 +9,6 @@ ARCHS = x86_64
 EPSILON_SIMULATOR_HAS_LIBPNG = 1
 
 ifdef ARCH
-EXE = bin
 BUILD_DIR := $(BUILD_DIR)/$(ARCH)
 else
 HANDY_TARGETS_EXTENSIONS = app