简介
打算是用buildroot把gcc安装到树莓派中，然后查了下发现，buildroot从2012.11版本就不支持这么做了，如果要实现，需要自己加补丁
补丁
commit链接
https://github.com/copyright1999/raspi4b-project/commit/210f3526b47227b7e5f6f59d03dbb8f136afd161
补丁1
buildroot/package/gcc/Config.in文件末尾添加这一段
config BR2_PACKAGE_GCC_TARGET
bool "gcc"
depends on BR2_TOOLCHAIN_BUILDROOT
select BR2_PACKAGE_BINUTILS
select BR2_PACKAGE_BINUTILS_TARGET
select BR2_PACKAGE_GMP
select BR2_PACKAGE_MPFR
select BR2_PACKAGE_MPC
help
If you want the target system to be able to run
binutils/gcc and compile native code, say Y here.
config BR2_EXTRA_TARGET_GCC_CONFIG_OPTIONS
string "Additional target gcc options"
default ""
depends on BR2_PACKAGE_GCC_TARGET
help
Any additional target gcc options you may want to include....
Including, but not limited to --disable-checking etc.
Refer to */configure in your gcc sources.
补丁2
增加buildroot/package/gcc/gcc-target.mk文件
################################################################################
#
# gcc-target
#
################################################################################
GCC_TARGET_VERSION = $(GCC_VERSION)
GCC_TARGET_SITE = $(GCC_SITE)
GCC_TARGET_SOURCE = $(GCC_SOURCE)
# Use the same archive as gcc-initial and gcc-final
GCC_TARGET_DL_SUBDIR = gcc
GCC_TARGET_DEPENDENCIES = gmp mpfr mpc
# First, we use HOST_GCC_COMMON_MAKE_OPTS to get a lot of correct flags (such as
# the arch, abi, float support, etc.) which are based on the config used to
# build the internal toolchain
GCC_TARGET_CONF_OPTS = $(HOST_GCC_COMMON_CONF_OPTS)
# Then, we modify incorrect flags from HOST_GCC_COMMON_CONF_OPTS
GCC_TARGET_CONF_OPTS += \
--with-sysroot=/ \
--with-build-sysroot=$(STAGING_DIR) \
--disable-__cxa_atexit \
--with-gmp=$(STAGING_DIR) \
--with-mpc=$(STAGING_DIR) \
--with-mpfr=$(STAGING_DIR)
# Then, we force certain flags that may appear in HOST_GCC_COMMON_CONF_OPTS
GCC_TARGET_CONF_OPTS += \
--disable-libquadmath \
--disable-libsanitizer \
--disable-plugin \
--disable-lto
# Finally, we add some of our own flags
GCC_TARGET_CONF_OPTS += \
--enable-languages=c \
--disable-boostrap \
--disable-libgomp \
--disable-nls \
--disable-libmpx \
--disable-gcov \
$(EXTRA_TARGET_GCC_CONFIG_OPTIONS)
GCC_TARGET_CONF_ENV = $(HOST_GCC_COMMON_CONF_ENV)
GCC_TARGET_MAKE_OPTS += $(HOST_GCC_COMMON_MAKE_OPTS)
# Install standard C headers (from glibc)
define GCC_TARGET_INSTALL_HEADERS
cp -r $(STAGING_DIR)/usr/include $(TARGET_DIR)/usr
endef
GCC_TARGET_POST_INSTALL_TARGET_HOOKS += GCC_TARGET_INSTALL_HEADERS
GCC_TARGET_GLIBC_LIBS = \
libBrokenLocale.so libanl.so libbfd.so libc.so libcrypt.so libdl.so \
libm.so libnss_compat.so libnss_db.so libnss_files.so libnss_hesiod.so \
libpthread.so libresolv.so librt.so libthread_db.so libutil.so
# Install standard C libraries (from glibc)
define GCC_TARGET_INSTALL_LIBS
for libpattern in $(GCC_TARGET_GLIBC_LIBS); do \
$(call copy_toolchain_lib_root,$$libpattern) ; \
done
cp -dpf $(STAGING_DIR)/usr/lib/*crt*.o $(TARGET_DIR)/usr/lib/
cp -dpf $(STAGING_DIR)/usr/lib/*_nonshared.a $(TARGET_DIR)/usr/lib/
endef
GCC_TARGET_POST_INSTALL_TARGET_HOOKS += GCC_TARGET_INSTALL_LIBS
# Remove unnecessary files (extra links to gcc binaries, and libgcc which is
# already in `/lib`)
define GCC_TARGET_RM_FILES
rm -f $(TARGET_DIR)/usr/bin/$(ARCH)-buildroot-linux-gnu-gcc*
rm -f $(TARGET_DIR)/usr/lib/libgcc_s*.so*
rm -f $(TARGET_DIR)/usr/$(ARCH)-buildroot-linux-gnu/lib/ldscripts/elf32*
rm -f $(TARGET_DIR)/usr/$(ARCH)-buildroot-linux-gnu/lib/ldscripts/elf64b*
endef
GCC_TARGET_POST_INSTALL_TARGET_HOOKS += GCC_TARGET_RM_FILES
$(eval $(autotools-package))
补丁3
增加buildroot/package/gcc-target/gcc-target.hash文件，直接链接buildroot/package/gcc/gcc.hash
补丁4
修改buildroot/Makefile文件
buildroot配置
make menuconfig，勾选上这三个选项，记住一定要勾选Enable C++ support选项
配置好后，最好先make distclean一下，再去make
运行结果
编译成功
安装到树莓派4B的板子上，运行成功
遇到的问题
在编译的过程，碰到了wsl的OOM问题，可以看到有个Killed singal，是进程被kill的
dmesg一看不出所料
一般这种编译工具链，比如GCC，LLVM都需要机器的内存足够大，而我的wsl分配了4G，显然不够
把内存改成了8G之后就顺利编译通过了
