2. Linux From Scratch 12.3
3. part3intro_toolchaintechnotes
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	Translation	Source string	Target string
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	The LFS book is not (and does not contain) a general tutorial to build a cross- (or native) toolchain. Don't use the commands in the book for a cross-toolchain for some purpose other than building LFS, unless you really understand what you are doing.
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	All the cross-compiled packages in this book use an autoconf-based building system. The autoconf-based building system accepts system types in the form cpu-vendor-kernel-os, referred to as the system triplet. Since the vendor field is often irrelevant, autoconf lets you omit it.
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	An astute reader may wonder why a <quote>triplet</quote> refers to a four component name. The kernel field and the os field began as a single <quote>system</quote> field. Such a three-field form is still valid today for some systems, for example, <literal>x86_64-unknown-freebsd</literal>. But two systems can share the same kernel and still be too different to use the same triplet to describe them. For example, Android running on a mobile phone is completely different from Ubuntu running on an ARM64 server, even though they are both running on the same type of CPU (ARM64) and using the same kernel (Linux).
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	Without an emulation layer, you cannot run an executable for a server on a mobile phone or vice versa. So the <quote>system</quote> field has been divided into kernel and os fields, to designate these systems unambiguously. In our example, the Android system is designated <literal>aarch64-unknown-linux-android</literal>, and the Ubuntu system is designated <literal>aarch64-unknown-linux-gnu</literal>.
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	The word <quote>triplet</quote> remains embedded in the lexicon. A simple way to determine your system triplet is to run the <command>config.guess</command> script that comes with the source for many packages. Unpack the binutils sources, run the script <userinput>./config.guess</userinput>, and note the output. For example, for a 32-bit Intel processor the output will be <emphasis>i686-pc-linux-gnu</emphasis>. On a 64-bit system it will be <emphasis>x86_64-pc-linux-gnu</emphasis>. On most Linux systems the even simpler <command>gcc -dumpmachine</command> command will give you similar information.
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	Generally speaking, cc-lfs cannot run on pc (the host system). Even though the triplets for pc and lfs are compatible with each other, an executable for lfs must depend on glibc-&glibc-version;; the host distro may utilize either a different implementation of libc (for example, musl), or a previous release of glibc (for example, glibc-2.13).
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	Even if cc-lfs can run on pc, using it on pc would create a risk of linking to the pc libraries, since cc-lfs is a native compiler.
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	So when we build gcc stage 2, we instruct the building system to rebuild libgcc and libstdc++ with cc1, but we link libstdc++ to the newly rebuilt libgcc instead of the old, degraded build. This makes the rebuilt libstdc++ fully functional.
	Linux From Scratch 12.3/part3intro_toolchaintechnotes — Chinese (Simplified Han script)	In &ch-final; (or <quote>stage 3</quote>), all the packages needed for the LFS system are built. Even if a package has already been installed into the LFS system in a previous chapter, we still rebuild the package. The main reason for rebuilding these packages is to make them stable: if we reinstall an LFS package on a completed LFS system, the reinstalled content of the package should be the same as the content of the same package when first installed in &ch-final;. The temporary packages installed in &ch-tmp-cross; or &ch-tmp-chroot; cannot satisfy this requirement, because some of them are built without optional dependencies, and autoconf cannot perform some feature checks in &ch-tmp-cross; because of cross-compilation, causing the temporary packages to lack optional features, or use suboptimal code routines. Additionally, a minor reason for rebuilding the packages is to run the test suites.