Rebuild deps/ and src/ when ARCH changes

This change moves the build instructions for dependencies to a separate
Makefile in deps/. The ARCH environment variable is stored in a
.make-arch file in the same directory as the Makefile. The contents of
this file is read and compared to the current ARCH, and, on a mismatch
triggers rebuilding the entire source tree.

When file .make-arch exists and matches with ARCH from the environment,
the dependencies are assumed to already be built.

The new "clean" target only cleans the Redis source tree, not its
dependencies. To clear the dependencies as well, the "distclean" target
can be used.

.gitignore

@@ -22,3 +22,4 @@ src/redis.conf
 deps/lua/src/lua
 deps/lua/src/luac
 deps/lua/src/liblua.a
+.make-*

deps/Makefile

+# Redis dependency Makefile
+
+UNAME_S:=$(shell sh -c 'uname -s 2> /dev/null || echo not')
+
+LUA_CFLAGS=-O2 -Wall $(ARCH)
+ifeq ($(UNAME_S),SunOS)
+  # Make isinf() available
+  LUA_CFLAGS+= -D__C99FEATURES__=1
+endif
+
+JEMALLOC_CFLAGS=
+ifeq ($(ARCH),-m32)
+  JEMALLOC_CFLAGS+=CFLAGS="-std=gnu99 -Wall -pipe -g3 -fvisibility=hidden -O3 -funroll-loops -m32"
+endif
+
+CCCOLOR="\033[34m"
+LINKCOLOR="\033[34;1m"
+SRCCOLOR="\033[33m"
+BINCOLOR="\033[37;1m"
+MAKECOLOR="\033[32;1m"
+ENDCOLOR="\033[0m"
+
+default:
+	@echo "Explicit target required"
+
+# Clean everything when ARCH is different
+ifneq ($(shell sh -c '[ -f .make-arch ] && cat .make-arch'), $(ARCH))
+.make-arch: distclean
+else
+.make-arch:
+endif
+
+.make-arch:
+	-(echo $(ARCH) > .make-arch)
+
+distclean:
+	-(cd hiredis && $(MAKE) clean) > /dev/null || true
+	-(cd linenoise && $(MAKE) clean) > /dev/null || true
+	-(cd lua && $(MAKE) clean) > /dev/null || true
+	-(cd jemalloc && [ -f Makefile ] && $(MAKE) distclean) > /dev/null || true
+	-(rm -f .make-arch)
+
+hiredis: .make-arch
+	@printf '%b %b\n' $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)hiredis$(ENDCOLOR)
+	cd hiredis && $(MAKE) static ARCH="$(ARCH)"
+
+linenoise: .make-arch
+	@printf '%b %b\n' $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)linenoise$(ENDCOLOR)
+	cd linenoise && $(MAKE) ARCH="$(ARCH)"
+
+lua: .make-arch
+	@printf '%b %b\n' $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)lua$(ENDCOLOR)
+	cd lua && $(MAKE) CFLAGS="$(LUA_CFLAGS)" MYLDFLAGS="$(ARCH)" ansi
+
+jemalloc: .make-arch
+	@printf '%b %b\n' $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)jemalloc$(ENDCOLOR)
+	cd jemalloc && ./configure $(JEMALLOC_CFLAGS) --with-jemalloc-prefix=je_ --enable-cc-silence && $(MAKE) lib/libjemalloc.a
+
+.PHONY: default conditional_clean hiredis linenoise lua jemalloc

src/Makefile

@@ -5,8 +5,7 @@
 release_hdr := $(shell sh -c './mkreleasehdr.sh')
 uname_S := $(shell sh -c 'uname -s 2>/dev/null || echo not')
 OPTIMIZATION?=-O2
-
-LUA_CFLAGS=-O2 -Wall
+DEPENDENCY_TARGETS=hiredis linenoise lua
 
 ifeq ($(uname_S),Linux)
   ifneq ($(FORCE_LIBC_MALLOC),yes)
@@ -15,8 +14,6 @@ ifeq ($(uname_S),Linux)
 endif
 
 ifeq ($(uname_S),SunOS)
-  # make isinf() available
-  LUA_CFLAGS+=-D__C99FEATURES__=1
   CFLAGS?=-std=c99 -pedantic $(OPTIMIZATION) -Wall -W -D__EXTENSIONS__ -D_XPG6
   CCLINK?=-ldl -lnsl -lsocket -lm -lpthread
   DEBUG?=-g -ggdb 
@@ -27,27 +24,23 @@ else
 endif
 
 ifeq ($(USE_TCMALLOC),yes)
-  ALLOD_DEPS=
   ALLOC_LINK=-ltcmalloc
   ALLOC_FLAGS=-DUSE_TCMALLOC
 endif
 
 ifeq ($(USE_TCMALLOC_MINIMAL),yes)
-  ALLOD_DEPS=
   ALLOC_LINK=-ltcmalloc_minimal
   ALLOC_FLAGS=-DUSE_TCMALLOC
 endif
 
 ifeq ($(USE_JEMALLOC),yes)
-  ALLOC_DEP=../deps/jemalloc/lib/libjemalloc.a
-  ALLOC_LINK=$(ALLOC_DEP) -ldl
+  ALLOC_LINK=../deps/jemalloc/lib/libjemalloc.a -ldl
   ALLOC_FLAGS=-DUSE_JEMALLOC -I../deps/jemalloc/include
+  DEPENDENCY_TARGETS+= jemalloc
 endif
 
 CCLINK+= $(ALLOC_LINK)
 CFLAGS+= $(ALLOC_FLAGS)
-LUA_CFLAGS+= $(ARCH)
-
 CCOPT= $(CFLAGS) $(ARCH) $(PROF)
 
 PREFIX= /usr/local
@@ -160,52 +153,52 @@ ziplist.o: ziplist.c zmalloc.h util.h ziplist.h endian.h
 zipmap.o: zipmap.c zmalloc.h endian.h
 zmalloc.o: zmalloc.c config.h zmalloc.h
 
-.PHONY: dependencies
-
-dependencies:
-	@printf '%b %b\n' $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)hiredis$(ENDCOLOR)
-	@cd ../deps/hiredis && $(MAKE) static ARCH="$(ARCH)"
-	@printf '%b %b\n' $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)linenoise$(ENDCOLOR)
-	@cd ../deps/linenoise && $(MAKE) ARCH="$(ARCH)"
-	@echo $(MAKECOLOR)MAKE$(ENDCOLOR) $(BINCOLOR)Lua ansi$(ENDCOLOR)
-	@cd ../deps/lua && $(MAKE) CFLAGS="$(LUA_CFLAGS)" MYLDFLAGS="$(ARCH)" ansi
+# Clean local objects when ARCH is different
+ifneq ($(shell sh -c '[ -f .make-arch ] && cat .make-arch'), $(ARCH))
+.make-arch: clean
+else
+.make-arch:
+endif
 
-../deps/jemalloc/lib/libjemalloc.a:
-	cd ../deps/jemalloc && ./configure $(JEMALLOC_CFLAGS) --with-jemalloc-prefix=je_ --enable-cc-silence && $(MAKE) lib/libjemalloc.a
+.make-arch:
+	-(cd ../deps && make $(DEPENDENCY_TARGETS) ARCH="$(ARCH)")
+	-(echo $(ARCH) > .make-arch)
 
-redis-server: dependencies $(OBJ)
+redis-server: .make-arch $(OBJ)
 	$(QUIET_LINK)$(CC) -o $(PRGNAME) $(CCOPT) $(DEBUG) $(OBJ) ../deps/lua/src/liblua.a $(CCLINK)
 
-redis-benchmark: dependencies $(BENCHOBJ)
-	@cd ../deps/hiredis && $(MAKE) static
+redis-benchmark: .make-arch $(BENCHOBJ)
 	$(QUIET_LINK)$(CC) -o $(BENCHPRGNAME) $(CCOPT) $(DEBUG) $(BENCHOBJ) ../deps/hiredis/libhiredis.a $(CCLINK)
 
-redis-benchmark.o:
+redis-benchmark.o: redis-benchmark.c .make-arch
 	$(QUIET_CC)$(CC) -c $(CFLAGS) -I../deps/hiredis $(DEBUG) $(COMPILE_TIME) $<
 
-redis-cli: dependencies $(CLIOBJ)
+redis-cli: .make-arch $(CLIOBJ)
 	$(QUIET_LINK)$(CC) -o $(CLIPRGNAME) $(CCOPT) $(DEBUG) $(CLIOBJ) ../deps/hiredis/libhiredis.a ../deps/linenoise/linenoise.o $(CCLINK)
 
-redis-cli.o:
+redis-cli.o: redis-cli.c .make-arch
 	$(QUIET_CC)$(CC) -c $(CFLAGS) -I../deps/hiredis -I../deps/linenoise $(DEBUG) $(COMPILE_TIME) $<
 
-redis-check-dump: $(CHECKDUMPOBJ)
+redis-check-dump: .make-arch $(CHECKDUMPOBJ)
 	$(QUIET_LINK)$(CC) -o $(CHECKDUMPPRGNAME) $(CCOPT) $(DEBUG) $(CHECKDUMPOBJ) $(CCLINK)
 
-redis-check-aof: $(CHECKAOFOBJ)
+redis-check-aof: .make-arch $(CHECKAOFOBJ)
 	$(QUIET_LINK)$(CC) -o $(CHECKAOFPRGNAME) $(CCOPT) $(DEBUG) $(CHECKAOFOBJ) $(CCLINK)
 
 # Because the jemalloc.h header is generated as a part of the jemalloc build
-# process, building it should complete before building any other object.
-%.o: %.c $(ALLOC_DEP)
+# process, building it should complete before building any other object. Instead of
+# depending on a single artifact, simply build all dependencies first.
+%.o: %.c .make-arch
 	$(QUIET_CC)$(CC) -c $(CFLAGS) $(DEBUG) $(COMPILE_TIME) -I../deps/lua/src $<
 
+.PHONY: all clean distclean
+
 clean:
 	rm -rf $(PRGNAME) $(BENCHPRGNAME) $(CLIPRGNAME) $(CHECKDUMPPRGNAME) $(CHECKAOFPRGNAME) *.o *.gcda *.gcno *.gcov
-	cd ../deps/hiredis && $(MAKE) $@
-	cd ../deps/linenoise && $(MAKE) $@
-	cd ../deps/lua && $(MAKE) $@
-	-(cd ../deps/jemalloc && $(MAKE) distclean)
+
+distclean: clean
+	-(cd ../deps && $(MAKE) distclean)
+	-(rm -f .make-arch)
 
 dep:
 	$(CC) -MM *.c -I ../deps/hiredis -I ../deps/linenoise