#
# This file implements the support for external toolchains, i.e
# toolchains that have not been produced by Buildroot itself and that
# are already available on the system on which Buildroot runs. So far,
# we have tested this with:
#
# * Toolchains generated by Crosstool-NG
# * Toolchains generated by Buildroot
# * ARM, MIPS and PowerPC toolchains made available by
# Codesourcery. For the MIPS toolchain, the -muclibc variant isn't
# supported yet, only the default glibc-based variant is.
#
# The basic principle is the following
#
# 1. Perform some checks on the conformity between the toolchain
# configuration described in the Buildroot menuconfig system, and the
# real configuration of the external toolchain. This is for example
# important to make sure that the Buildroot configuration system
# knows whether the toolchain supports RPC, IPv6, locales, large
# files, etc. Unfortunately, these things cannot be detected
# automatically, since the value of these options (such as
# BR2_INET_RPC) are needed at configuration time because these
# options are used as dependencies for other options. And at
# configuration time, we are not able to retrieve the external
# toolchain configuration.
#
# 2. Copy the libraries needed at runtime to the target directory,
# $(TARGET_DIR). Obviously, things such as the C library, the dynamic
# loader and a few other utility libraries are needed if dynamic
# applications are to be executed on the target system.
#
# 3. Copy the libraries and headers to the staging directory. This
# will allow all further calls to gcc to be made using --sysroot
# $(STAGING_DIR), which greatly simplifies the compilation of the
# packages when using external toolchains. So in the end, only the
# cross-compiler binaries remains external, all libraries and headers
# are imported into the Buildroot tree.
uclibc: dependencies $(STAMP_DIR)/ext-toolchain-installed
LIB_EXTERNAL_LIBS=ld*.so libc.so libcrypt.so libdl.so libgcc_s.so libm.so libnsl.so libresolv.so librt.so libutil.so
ifeq ($(BR2_TOOLCHAIN_EXTERNAL_GLIBC),y)
LIB_EXTERNAL_LIBS+=libnss_files.so libnss_dns.so
endif
ifeq ($(BR2_INSTALL_LIBSTDCPP),y)
USR_LIB_EXTERNAL_LIBS+=libstdc++.so
endif
ifneq ($(BR2_PTHREADS_NONE),y)
LIB_EXTERNAL_LIBS+=libpthread.so
ifeq ($(BR2_PACKAGE_GDB_SERVER),y)
LIB_EXTERNAL_LIBS+=libthread_db.so
endif # gdbserver
endif # ! no threads
# SYSROOT_DIR selection. We first try the -print-sysroot option,
# available in gcc 4.4.x and in some Codesourcery toolchains. If this
# option is not available, we fallback to the value of --with-sysroot
# as visible in CROSS-gcc -v. We don't pass any option to gcc that
# could select a multilib variant as we want the "main" sysroot, which
# contains all variants of the C library in the case of multilib
# toolchains.
TARGET_CC_NO_SYSROOT=$(filter-out --sysroot=%,$(TARGET_CC_NOCCACHE))
SYSROOT_DIR=$(shell $(TARGET_CC_NO_SYSROOT) -print-sysroot 2>/dev/null)
ifeq ($(SYSROOT_DIR),)
SYSROOT_DIR=$(shell readlink -f $$(LANG=C $(TARGET_CC_NO_SYSROOT) -print-file-name=libc.a) |sed -r -e 's:usr/lib/libc\.a::;')
endif
# Now, find if the toolchain specifies a sub-directory for the
# specific architecture variant we're interested in. This is the case
# with multilib toolchain, when the selected architecture variant is
# not the default one. To do so, we ask the compiler by passing all
# flags, except the --sysroot flag since we want to the compiler to
# tell us where its original sysroot is. ARCH_SUBDIR will contain the
# subdirectory, in the main SYSROOT_DIR, that corresponds to the
# selected architecture variant. ARCH_SYSROOT_DIR will contain the
# full path to this location.
ARCH_SUBDIR=$(shell $(TARGET_CC_NO_SYSROOT) $(TARGET_CFLAGS) -print-multi-directory)
ARCH_SYSROOT_DIR=$(SYSROOT_DIR)/$(ARCH_SUBDIR)
$(STAMP_DIR)/ext-toolchain-installed:
@echo "Checking external toolchain settings"
$(Q)$(call check_cross_compiler_exists)
ifeq ($(strip $(SYSROOT_DIR)),)
@echo "External toolchain doesn't support --sysroot. Cannot use."
exit 1
endif
ifeq ($(BR2_arm),y)
$(Q)$(call check_arm_abi)
endif
ifeq ($(BR2_INSTALL_LIBSTDCPP),y)
$(Q)$(call check_cplusplus)
endif
ifeq ($(BR2_TOOLCHAIN_EXTERNAL_UCLIBC),y)
$(Q)$(call check_uclibc,$(SYSROOT_DIR))
else
$(Q)$(call check_glibc,$(SYSROOT_DIR))
endif
mkdir -p $(TARGET_DIR)/lib
@echo "Copy external toolchain libraries to target..."
$(Q)for libs in $(LIB_EXTERNAL_LIBS); do \
$(call copy_toolchain_lib_root,$(ARCH_SYSROOT_DIR),$$libs,/lib,$(BR2_TOOLCHAIN_EXTERNAL_STRIP)); \
done
$(Q)for libs in $(USR_LIB_EXTERNAL_LIBS); do \
$(call copy_toolchain_lib_root,$(ARCH_SYSROOT_DIR),$$libs,/usr/lib,$(BR2_TOOLCHAIN_EXTERNAL_STRIP)); \
done
@echo "Copy external toolchain sysroot to staging..."
$(Q)$(call copy_toolchain_sysroot,$(SYSROOT_DIR),$(ARCH_SYSROOT_DIR),$(ARCH_SUBDIR))
# Create lib64 symbolic links if needed
$(Q)if [ -L $(ARCH_SYSROOT_DIR)/lib64 ] ; then \
$(call create_lib64_symlinks) ; \
fi
@touch $@
