genode/repos/base/mk/lib.mk
Christian Helmuth 861508ad68 Always recreate library archives
GNU ar only uses a flat module (object) name space but supports multiple
instances of objects with the same name. As we use subdirectories with
source file names that may clash (e.g., signal/common.cc and
server/common.cc in the base library) some of our static library
archives have multiple object instances. This is not an issue on archive
creation but works not as expected when updating archives. To avoid
updates of library archives we delete the files before calling GNU ar.
2016-05-09 13:10:52 +02:00

219 lines
5.8 KiB
Makefile

##
## Rules for building a library target
##
## The following variables must be passed when calling this file:
##
## BASE_DIR - base directory of the build system
## REPOSITORIES - repositories providing libs and headers
## VERBOSE - build verboseness modifier
## VERBOSE_DIR - verboseness modifier for changing directories
## VERBOSE_MK - verboseness of make calls
## BUILD_BASE_DIR - base of build directory tree
## LIB_CACHE_DIR - library build cache location
## INSTALL_DIR - program target build directory
## DEPS - library dependencies
## REP_DIR - repository where the library resides
## CONTRIB_DIR - location of ported 3rd-party source codes
##
include $(BASE_DIR)/mk/base-libs.mk
#
# Prevent <libname>.mk rules to be executed as default rule
#
all:
#
# Make a rlib or dylib instead of object file
#
ifndef SHARED_LIB
CC_RUSTC_OPT += --crate-type rlib
else
CC_RUSTC_OPT += --crate-type dylib
endif
#
# Include common utility functions
#
include $(BASE_DIR)/mk/util.inc
#
# Include specifics, for example platform, kernel-api etc.
#
include $(SPEC_FILES)
#
# Include library build instructions
#
# We set the 'called_from_lib_mk' variable to allow the library description file
# to respond to the build pass.
#
BACKUP_INC_DIR := $(INC_DIR)
called_from_lib_mk = yes
include $(LIB_MK)
#
# Sanity check for INC_DIR overrides
#
ifneq ($(filter-out $(INC_DIR),$(BACKUP_INC_DIR)),)
all: error_inc_dir_override
endif
error_inc_dir_override:
@$(ECHO) "Error: $(LIB_MK) overrides INC_DIR instead of appending" ; false
#
# Include lib-import descriptions of all used libraries and the target library
#
include $(foreach LIB,$(LIBS),$(call select_from_repositories,lib/import/import-$(LIB).mk))
#
# Include global definitions
#
include $(BASE_DIR)/mk/global.mk
#
# Name of <libname>.lib.a or <libname>.lib.so file to create
#
ifdef SHARED_LIB
LIB_SO := $(addsuffix .lib.so,$(LIB))
INSTALL_SO := $(INSTALL_DIR)/$(LIB_SO)
LIB_FILENAME := $(LIB_SO)
else ifdef SRC_RS
LIB_RLIB := $(addsuffix .rlib,$(LIB))
LIB_FILENAME := $(LIB_RLIB)
else
LIB_A := $(addsuffix .lib.a,$(LIB))
LIB_FILENAME := $(LIB_A)
endif
LIB_TAG := $(addsuffix .lib.tag,$(LIB))
#
# Link libgcc to shared libraries
#
# For static libraries, libgcc is not needed because it will be linked
# against the final target.
#
ifdef SHARED_LIB
LIBGCC = $(shell $(CC) $(CC_MARCH) -print-libgcc-file-name)
endif
#
# Build libraries position-independent
#
# This option is required for building shared objects but also for static
# libraries that are (potentially) linked against shared objects. Hence,
# we build all libraries with '-fPIC'.
#
CC_OPT_PIC ?= -fPIC
CC_OPT += $(CC_OPT_PIC)
#
# Print message for the currently built library
#
all: message
message:
$(MSG_LIB)$(LIB)
#
# Trigger the creation of the <libname>.lib.a or <libname>.lib.so file
#
all: $(LIB_TAG)
#
# Trigger the build of host tools
#
# We make '$(LIB_TAG)' depend on the host tools to support building host tools
# from pseudo libraries with no actual source code. In this case '$(OBJECTS)'
# is empty.
#
$(LIB_TAG) $(OBJECTS): $(HOST_TOOLS)
$(LIB_TAG): $(LIB_A) $(LIB_SO) $(INSTALL_SO) $(LIB_RLIB)
@touch $@
include $(BASE_DIR)/mk/generic.mk
#
# Rule to build the <libname>.lib.a file
#
# Use $(OBJECTS) instead of $^ for specifying the list of objects to include
# in the archive because $^ may also contain non-object phony targets, e.g.,
# used by the integration of Qt's meta-object compiler into the Genode
# build system.
#
$(LIB_A): $(OBJECTS)
$(MSG_MERGE)$(LIB_A)
$(VERBOSE)$(RM) -f $@
$(VERBOSE)$(AR) -rcs $@ $(OBJECTS)
#
# Rename from object to rlib
#
$(LIB_RLIB): $(OBJECTS)
$(MSG_RENAME)$(LIB_RLIB)
$(VERBOSE)cp $(OBJECTS) $(LIB_RLIB)
#
# Don't link base libraries against shared libraries except for ld.lib.so
#
ifdef SHARED_LIB
ifneq ($(LIB),$(DYNAMIC_LINKER))
override DEPS := $(filter-out $(BASE_LIBS:=.lib),$(DEPS))
endif
endif
#
# The 'sort' is needed to ensure the same link order regardless
# of the find order, which uses to vary among different systems.
#
STATIC_LIBS := $(foreach l,$(DEPS:.lib=),$(LIB_CACHE_DIR)/$l/$l.lib.a)
STATIC_LIBS := $(sort $(wildcard $(STATIC_LIBS)))
STATIC_LIBS_BRIEF := $(subst $(LIB_CACHE_DIR),$$libs,$(STATIC_LIBS))
#
# Rule to build the <libname>.lib.so file
#
# The 'LIBS' variable may contain static and shared sub libraries. When linking
# the shared library, we have to link all shared sub libraries to the library
# to store the library-dependency information in the library. Because we do not
# know which sub libraries are static or shared prior calling 'build_libs.mk',
# we use an explicit call to the 'lib_so_wildcard' macro to determine the subset
# of libraries that are shared.
#
# The 'ldso-startup/startup.o' object file, which contains the support code for
# constructing static objects must be specified as object file to prevent the
# linker from garbage-collecting it.
#
USED_SHARED_LIBS := $(filter $(DEPS:.lib=),$(SHARED_LIBS))
USED_SO_FILES := $(foreach s,$(USED_SHARED_LIBS),$(LIB_CACHE_DIR)/$s/$s.lib.so)
#
# Don't link ld libary against shared objects
#
USED_SO_FILES := $(filter-out %$(DYNAMIC_LINKER).lib.so,$(USED_SO_FILES))
#
# Default entry point of shared libraries
#
ENTRY_POINT ?= 0x0
$(LIB_SO): $(STATIC_LIBS) $(OBJECTS) $(wildcard $(LD_SCRIPT_SO))
$(MSG_MERGE)$(LIB_SO)
$(VERBOSE)libs=$(LIB_CACHE_DIR); $(LD) -o $(LIB_SO) -shared --eh-frame-hdr \
$(LD_OPT) \
-T $(LD_SCRIPT_SO) \
--entry=$(ENTRY_POINT) \
--whole-archive \
--start-group \
$(USED_SO_FILES) $(STATIC_LIBS_BRIEF) $(OBJECTS) \
--end-group \
--no-whole-archive \
$(LIBGCC)
$(INSTALL_SO):
$(VERBOSE)ln -sf $(CURDIR)/$(LIB_SO) $@