Linux From Scratch - Version 6.0

Chapter 5. Constructing a Temporary System

5.4. Binutils-2.15.91.0.2 - Pass 1

The Binutils package contains a linker, an assembler, and other tools for handling object files.

Approximate build time: 1.0 SBU

Required disk space: 194 MB

Binutils installation depends on: Bash, Coreutils, Diffutils, GCC, Gettext, Glibc, Grep, Make, Perl, Sed, and Texinfo

5.4.1. Installation of Binutils

It is important that Binutils be the first package compiled because both Glibc and GCC perform various tests on the available linker and assembler to determine which of their own features to enable.

This package is known to have issues when its default optimization flags (including the -march and -mcpu options) are changed. If any environment variables that override default optimizations have been defined, such as CFLAGS and CXXFLAGS, unset them when building Binutils.

The Binutils documentation recommends building Binutils outside of the source directory in a dedicated build directory: 

mkdir ../binutils-build
cd ../binutils-build
[Note]

Note

In order for the SBU values listed in the rest of the book to be of any use, measure the time it takes to build this package from the configuration, up to and including the first install. To achieve this easily, wrap the four commands in a time command like this: time { ./configure ... && ... && ... && make install; }.

Now prepare Binutils for compilation: 

../binutils-2.15.91.0.2/configure --prefix=/tools \
    --disable-nls

The meaning of the configure options:

--prefix=/tools

This tells the configure script to prepare to install the Binutils programs in the /tools directory.

--disable-nls

This disables internationalization. This is not needed for the static programs, and NLS can cause problems when linking statically.

Continue with compiling the package: 

make configure-host
make LDFLAGS="-all-static"

The meaning of the make parameters:

configure-host

This forces all subdirectories to be configured immediately. A statically-linked build will fail without it. Use this option to work around the problem.

LDFLAGS="-all-static"

This tells the linker that all Binutils programs should be linked statically. However, strictly speaking, "-all-static" is passed to the libtool program, which then passes "-static" to the linker.

Compilation is now complete. Ordinarily we would now run the test suite, but at this early stage the test suite framework (Tcl, Expect, and DejaGNU) is not yet in place. The benefits of running the tests at this point are minimal since the programs from this first pass will soon be replaced by those from the second.

Install the package: 

make install

Next, prepare the linker for the “Adjusting” phase later on: 

make -C ld clean
make -C ld LDFLAGS="-all-static" LIB_PATH=/tools/lib

The meaning of the make parameters:

-C ld clean

This tells the make program to remove all compiled files in the ld subdirectory.

-C ld LDFLAGS="-all-static" LIB_PATH=/tools/lib

This option rebuilds everything in the ld subdirectory. Specifying the LIB_PATH Makefile variable on the command line allows us to override the default value and point it to the temporary tools location. The value of this variable specifies the linker's default library search path. This preparation is used later in the chapter.

[Warning]

Warning

Do not remove the Binutils build and source directories yet. These will be needed again in their current state later in this chapter.

Details on this package are located in Section 6.13.2, “Contents of Binutils.”