support out-of-tree build
this change adds support for building musl outside of the source
tree. the implementation is similar to autotools where running
configure in a different directory creates config.mak in the current
working directory and symlinks the makefile, which contains the
logic for creating all necessary directories and resolving paths
relative to the source directory.
to support both in-tree and out-of-tree builds with implicit make
rules, all object files are now placed into a separate directory.
diff --git a/Makefile b/Makefile
index df20f94..44b39b9 100644
--- a/Makefile
+++ b/Makefile
@@ -8,6 +8,7 @@
# Do not make changes here.
#
+srcdir = .
exec_prefix = /usr/local
bindir = $(exec_prefix)/bin
@@ -16,12 +17,16 @@
libdir = $(prefix)/lib
syslibdir = /lib
-SRCS = $(sort $(wildcard src/*/*.c arch/$(ARCH)/src/*.c))
-OBJS = $(SRCS:.c=.o)
+BASE_SRCS = $(sort $(wildcard $(srcdir)/src/*/*.c $(srcdir)/arch/$(ARCH)/src/*.c))
+BASE_OBJS = $(patsubst $(srcdir)/%.c,%.o,$(BASE_SRCS))
+ARCH_SRCS = $(wildcard $(srcdir)/src/*/$(ARCH)/*.s $(srcdir)/src/*/$(ARCH)$(ASMSUBARCH)/*.sub)
+ARCH_OBJS = $(patsubst $(srcdir)/%.sub,%.o,$(patsubst $(srcdir)/%.s,%.o,$(ARCH_SRCS)))
+REPLACED_OBJS = $(sort $(subst /$(ARCH)$(ASMSUBARCH)/,/,$(subst /$(ARCH)/,/,$(ARCH_OBJS))) $(subst /$(ARCH)$(ASMSUBARCH)/,/$(ARCH)/,$(subst /$(ARCH)/,/,$(ARCH_OBJS))))
+OBJS = $(addprefix obj/, $(filter-out $(REPLACED_OBJS), $(sort $(BASE_OBJS) $(ARCH_OBJS))))
LOBJS = $(OBJS:.o=.lo)
-GENH = include/bits/alltypes.h
-GENH_INT = src/internal/version.h
-IMPH = src/internal/stdio_impl.h src/internal/pthread_impl.h src/internal/libc.h
+GENH = obj/include/bits/alltypes.h
+GENH_INT = obj/src/internal/version.h
+IMPH = $(addprefix $(srcdir)/, src/internal/stdio_impl.h src/internal/pthread_impl.h src/internal/libc.h)
LDFLAGS =
LDFLAGS_AUTO =
@@ -32,7 +37,7 @@
CFLAGS_C99FSE = -std=c99 -ffreestanding -nostdinc
CFLAGS_ALL = $(CFLAGS_C99FSE)
-CFLAGS_ALL += -D_XOPEN_SOURCE=700 -I./arch/$(ARCH) -I./src/internal -I./include
+CFLAGS_ALL += -D_XOPEN_SOURCE=700 -I$(srcdir)/arch/$(ARCH) -Iobj/src/internal -I$(srcdir)/src/internal -Iobj/include -I$(srcdir)/include
CFLAGS_ALL += $(CPPFLAGS) $(CFLAGS_AUTO) $(CFLAGS)
CFLAGS_ALL_STATIC = $(CFLAGS_ALL)
CFLAGS_ALL_SHARED = $(CFLAGS_ALL) -fPIC -DSHARED
@@ -41,10 +46,11 @@
AR = $(CROSS_COMPILE)ar
RANLIB = $(CROSS_COMPILE)ranlib
-INSTALL = ./tools/install.sh
+INSTALL = $(srcdir)/tools/install.sh
-ARCH_INCLUDES = $(wildcard arch/$(ARCH)/bits/*.h)
-ALL_INCLUDES = $(sort $(wildcard include/*.h include/*/*.h) $(GENH) $(ARCH_INCLUDES:arch/$(ARCH)/%=include/%))
+ARCH_INCLUDES = $(wildcard $(srcdir)/arch/$(ARCH)/bits/*.h)
+INCLUDES = $(wildcard $(srcdir)/include/*.h $(srcdir)/include/*/*.h)
+ALL_INCLUDES = $(sort $(INCLUDES:$(srcdir)/%=%) $(GENH:obj/%=%) $(ARCH_INCLUDES:$(srcdir)/arch/$(ARCH)/%=include/%))
EMPTY_LIB_NAMES = m rt pthread crypt util xnet resolv dl
EMPTY_LIBS = $(EMPTY_LIB_NAMES:%=lib/lib%.a)
@@ -53,7 +59,7 @@
SHARED_LIBS = lib/libc.so
TOOL_LIBS = lib/musl-gcc.specs
ALL_LIBS = $(CRT_LIBS) $(STATIC_LIBS) $(SHARED_LIBS) $(EMPTY_LIBS) $(TOOL_LIBS)
-ALL_TOOLS = tools/musl-gcc
+ALL_TOOLS = obj/musl-gcc
WRAPCC_GCC = gcc
WRAPCC_CLANG = clang
@@ -62,91 +68,100 @@
-include config.mak
+ifeq ($(ARCH),)
+$(error Please set ARCH in config.mak before running make.)
+endif
+
all: $(ALL_LIBS) $(ALL_TOOLS)
+OBJ_DIRS = $(sort $(patsubst %/,%,$(dir $(ALL_LIBS) $(ALL_TOOLS) $(OBJS) $(GENH) $(GENH_INT))) $(addprefix obj/, crt crt/$(ARCH) include))
+
+$(ALL_LIBS) $(ALL_TOOLS) $(CRT_LIBS:lib/%=obj/crt/%) $(OBJS) $(LOBJS) $(GENH) $(GENH_INT): | $(OBJ_DIRS)
+
+$(OBJ_DIRS):
+ mkdir -p $@
+
install: install-libs install-headers install-tools
clean:
- rm -f crt/*.o
+ rm -f obj/crt/*.o obj/crt/$(ARCH)/*.o
rm -f $(OBJS)
rm -f $(LOBJS)
rm -f $(ALL_LIBS) lib/*.[ao] lib/*.so
rm -f $(ALL_TOOLS)
rm -f $(GENH) $(GENH_INT)
- rm -f include/bits
+ rm -f obj/include/bits/alltypes.h
distclean: clean
rm -f config.mak
-include/bits:
- @test "$(ARCH)" || { echo "Please set ARCH in config.mak before running make." ; exit 1 ; }
- ln -sf ../arch/$(ARCH)/bits $@
+obj/include/bits/alltypes.h: $(srcdir)/arch/$(ARCH)/bits/alltypes.h.in $(srcdir)/include/alltypes.h.in $(srcdir)/tools/mkalltypes.sed
+ sed -f $(srcdir)/tools/mkalltypes.sed $(srcdir)/arch/$(ARCH)/bits/alltypes.h.in $(srcdir)/include/alltypes.h.in > $@
-include/bits/alltypes.h.in: include/bits
+obj/src/internal/version.h: $(wildcard $(srcdir)/VERSION $(srcdir)/.git)
+ printf '#define VERSION "%s"\n' "$$(cd $(srcdir); sh tools/version.sh)" > $@
-include/bits/alltypes.h: include/bits/alltypes.h.in include/alltypes.h.in tools/mkalltypes.sed
- sed -f tools/mkalltypes.sed include/bits/alltypes.h.in include/alltypes.h.in > $@
+obj/src/internal/version.o obj/src/internal/version.lo: obj/src/internal/version.h
-src/internal/version.h: $(wildcard VERSION .git)
- printf '#define VERSION "%s"\n' "$$(sh tools/version.sh)" > $@
+obj/crt/rcrt1.o obj/src/ldso/dlstart.lo obj/src/ldso/dynlink.lo: $(srcdir)/src/internal/dynlink.h $(srcdir)/arch/$(ARCH)/reloc.h
-src/internal/version.o src/internal/version.lo: src/internal/version.h
+obj/crt/crt1.o obj/crt/scrt1.o obj/crt/rcrt1.o obj/src/ldso/dlstart.lo: $(srcdir)/arch/$(ARCH)/crt_arch.h
-crt/rcrt1.o src/ldso/dlstart.lo src/ldso/dynlink.lo: src/internal/dynlink.h arch/$(ARCH)/reloc.h
+obj/crt/rcrt1.o: $(srcdir)/src/ldso/dlstart.c
-crt/crt1.o crt/Scrt1.o crt/rcrt1.o src/ldso/dlstart.lo: $(wildcard arch/$(ARCH)/crt_arch.h)
+obj/crt/Scrt1.o obj/crt/rcrt1.o: CFLAGS_ALL += -fPIC
-crt/rcrt1.o: src/ldso/dlstart.c
+obj/crt/$(ARCH)/crti.o: $(srcdir)/crt/$(ARCH)/crti.s
-crt/Scrt1.o crt/rcrt1.o: CFLAGS_ALL += -fPIC
+obj/crt/$(ARCH)/crtn.o: $(srcdir)/crt/$(ARCH)/crtn.s
-OPTIMIZE_SRCS = $(wildcard $(OPTIMIZE_GLOBS:%=src/%))
-$(OPTIMIZE_SRCS:%.c=%.o) $(OPTIMIZE_SRCS:%.c=%.lo): CFLAGS += -O3
+OPTIMIZE_SRCS = $(wildcard $(OPTIMIZE_GLOBS:%=$(srcdir)/src/%))
+$(OPTIMIZE_SRCS:$(srcdir)/%.c=obj/%.o) $(OPTIMIZE_SRCS:$(srcdir)/%.c=obj/%.lo): CFLAGS += -O3
MEMOPS_SRCS = src/string/memcpy.c src/string/memmove.c src/string/memcmp.c src/string/memset.c
-$(MEMOPS_SRCS:%.c=%.o) $(MEMOPS_SRCS:%.c=%.lo): CFLAGS_ALL += $(CFLAGS_MEMOPS)
+$(MEMOPS_SRCS:%.c=obj/%.o) $(MEMOPS_SRCS:%.c=obj/%.lo): CFLAGS_ALL += $(CFLAGS_MEMOPS)
NOSSP_SRCS = $(wildcard crt/*.c) \
src/env/__libc_start_main.c src/env/__init_tls.c \
src/thread/__set_thread_area.c src/env/__stack_chk_fail.c \
src/string/memset.c src/string/memcpy.c \
src/ldso/dlstart.c src/ldso/dynlink.c
-$(NOSSP_SRCS:%.c=%.o) $(NOSSP_SRCS:%.c=%.lo): CFLAGS_ALL += $(CFLAGS_NOSSP)
+$(NOSSP_SRCS:%.c=obj/%.o) $(NOSSP_SRCS:%.c=obj/%.lo): CFLAGS_ALL += $(CFLAGS_NOSSP)
-$(CRT_LIBS:lib/%=crt/%): CFLAGS_ALL += -DCRT
+$(CRT_LIBS:lib/%=obj/crt/%): CFLAGS_ALL += -DCRT
# This incantation ensures that changes to any subarch asm files will
# force the corresponding object file to be rebuilt, even if the implicit
# rule below goes indirectly through a .sub file.
define mkasmdep
-$(dir $(patsubst %/,%,$(dir $(1))))$(notdir $(1:.s=.o)): $(1)
+$(patsubst $(srcdir)/%,obj/%,$(dir $(patsubst %/,%,$(dir $(1))))$(ARCH)$(ASMSUBARCH)/$(notdir $(1:.s=.o))): $(1)
endef
-$(foreach s,$(wildcard src/*/$(ARCH)*/*.s),$(eval $(call mkasmdep,$(s))))
+$(foreach s,$(wildcard $(srcdir)/src/*/$(ARCH)*/*.s),$(eval $(call mkasmdep,$(s))))
# Choose invocation of assembler to be used
# $(1) is input file, $(2) is output file, $(3) is assembler flags
ifeq ($(ADD_CFI),yes)
- AS_CMD = LC_ALL=C awk -f tools/add-cfi.common.awk -f tools/add-cfi.$(ARCH).awk $< | $(CC) -x assembler -c -o $@ -
+ AS_CMD = LC_ALL=C awk -f $(srcdir)/tools/add-cfi.common.awk -f $(srcdir)/tools/add-cfi.$(ARCH).awk $< | $(CC) -x assembler -c -o $@ -
else
AS_CMD = $(CC) -c -o $@ $<
endif
-%.o: $(ARCH)$(ASMSUBARCH)/%.sub
- $(CC) $(CFLAGS_ALL_STATIC) -c -o $@ $(dir $<)$(shell cat $<)
+obj/%.o: $(srcdir)/%.sub
+ $(CC) $(CFLAGS_ALL_STATIC) -c -o $@ $(dir $<)$$(cat $<)
-%.o: $(ARCH)/%.s
+obj/%.o: $(srcdir)/%.s
$(AS_CMD) $(CFLAGS_ALL_STATIC)
-%.o: %.c $(GENH) $(IMPH)
+obj/%.o: $(srcdir)/%.c $(GENH) $(IMPH)
$(CC) $(CFLAGS_ALL_STATIC) -c -o $@ $<
-%.lo: $(ARCH)$(ASMSUBARCH)/%.sub
- $(CC) $(CFLAGS_ALL_SHARED) -c -o $@ $(dir $<)$(shell cat $<)
+obj/%.lo: $(srcdir)/%.sub
+ $(CC) $(CFLAGS_ALL_SHARED) -c -o $@ $(dir $<)$$(cat $<)
-%.lo: $(ARCH)/%.s
+obj/%.lo: $(srcdir)/%.s
$(AS_CMD) $(CFLAGS_ALL_SHARED)
-%.lo: %.c $(GENH) $(IMPH)
+obj/%.lo: $(srcdir)/%.c $(GENH) $(IMPH)
$(CC) $(CFLAGS_ALL_SHARED) -c -o $@ $<
lib/libc.so: $(LOBJS)
@@ -163,21 +178,27 @@
rm -f $@
$(AR) rc $@
-lib/%.o: crt/%.o
+lib/%.o: obj/crt/%.o
cp $< $@
-lib/musl-gcc.specs: tools/musl-gcc.specs.sh config.mak
+lib/crti.o: obj/crt/$(ARCH)/crti.o
+ cp $< $@
+
+lib/crtn.o: obj/crt/$(ARCH)/crtn.o
+ cp $< $@
+
+lib/musl-gcc.specs: $(srcdir)/tools/musl-gcc.specs.sh config.mak
sh $< "$(includedir)" "$(libdir)" "$(LDSO_PATHNAME)" > $@
-tools/musl-gcc: config.mak
+obj/musl-gcc: config.mak
printf '#!/bin/sh\nexec "$${REALGCC:-$(WRAPCC_GCC)}" "$$@" -specs "%s/musl-gcc.specs"\n' "$(libdir)" > $@
chmod +x $@
-tools/%-clang: tools/%-clang.in config.mak
+obj/%-clang: $(srcdir)/tools/%-clang.in config.mak
sed -e 's!@CC@!$(WRAPCC_CLANG)!g' -e 's!@PREFIX@!$(prefix)!g' -e 's!@INCDIR@!$(includedir)!g' -e 's!@LIBDIR@!$(libdir)!g' -e 's!@LDSO@!$(LDSO_PATHNAME)!g' $< > $@
chmod +x $@
-$(DESTDIR)$(bindir)/%: tools/%
+$(DESTDIR)$(bindir)/%: obj/%
$(INSTALL) -D $< $@
$(DESTDIR)$(libdir)/%.so: lib/%.so
@@ -186,10 +207,13 @@
$(DESTDIR)$(libdir)/%: lib/%
$(INSTALL) -D -m 644 $< $@
-$(DESTDIR)$(includedir)/bits/%: arch/$(ARCH)/bits/%
+$(DESTDIR)$(includedir)/bits/%: $(srcdir)/arch/$(ARCH)/bits/%
$(INSTALL) -D -m 644 $< $@
-$(DESTDIR)$(includedir)/%: include/%
+$(DESTDIR)$(includedir)/bits/%: obj/include/bits/%
+ $(INSTALL) -D -m 644 $< $@
+
+$(DESTDIR)$(includedir)/%: $(srcdir)/include/%
$(INSTALL) -D -m 644 $< $@
$(DESTDIR)$(LDSO_PATHNAME): $(DESTDIR)$(libdir)/libc.so
@@ -199,12 +223,12 @@
install-headers: $(ALL_INCLUDES:include/%=$(DESTDIR)$(includedir)/%)
-install-tools: $(ALL_TOOLS:tools/%=$(DESTDIR)$(bindir)/%)
+install-tools: $(ALL_TOOLS:obj/%=$(DESTDIR)$(bindir)/%)
musl-git-%.tar.gz: .git
- git archive --format=tar.gz --prefix=$(patsubst %.tar.gz,%,$@)/ -o $@ $(patsubst musl-git-%.tar.gz,%,$@)
+ git --git-dir=$(srcdir)/.git archive --format=tar.gz --prefix=$(patsubst %.tar.gz,%,$@)/ -o $@ $(patsubst musl-git-%.tar.gz,%,$@)
musl-%.tar.gz: .git
- git archive --format=tar.gz --prefix=$(patsubst %.tar.gz,%,$@)/ -o $@ v$(patsubst musl-%.tar.gz,%,$@)
+ git --git-dir=$(srcdir)/.git archive --format=tar.gz --prefix=$(patsubst %.tar.gz,%,$@)/ -o $@ v$(patsubst musl-%.tar.gz,%,$@)
.PHONY: all clean install install-libs install-headers install-tools