diff --git a/chapter05/libstdc++.xml b/chapter05/libstdc++.xml index 42a304bfe..66128aa8a 100644 --- a/chapter05/libstdc++.xml +++ b/chapter05/libstdc++.xml @@ -63,8 +63,8 @@ cd build --host=$LFS_TGT \ --prefix=/tools \ --disable-multilib \ - --disable-nls \ - --disable-libstdcxx-threads \ + --disable-nls \ --disable-libstdcxx-pch \ --with-gxx-include-dir=/tools/$LFS_TGT/include/c++/&gcc-version; @@ -78,15 +78,15 @@ cd build instead of the one in /usr/bin. - + --disable-libstdcxx-pch diff --git a/prologue/architecture.xml b/prologue/architecture.xml index a6a456c83..f23d19cab 100644 --- a/prologue/architecture.xml +++ b/prologue/architecture.xml @@ -14,52 +14,37 @@ and x86_64 (64-bit) CPUs. On the other hand, the instructions in this book are also known to work, with some modifications, with the Power PC and ARM CPUs. To build a system that utilizes one of these CPUs, the main prerequisite, in -addition to those on the next few pages, is an existing Linux system such as an +addition to those on the next page, is an existing Linux system such as an earlier LFS installation, Ubuntu, Red Hat/Fedora, SuSE, or other distribution that targets the architecture that you have. Also note that a 32-bit distribution can be installed and used as a host system on a 64-bit AMD/Intel computer. -Some other facts about 64-bit systems need to be added here. When -compared to a 32-bit system, the sizes of executable programs are slightly -larger and the execution speeds of arbitrary programs are only slightly faster. -For example, in a test build of LFS-6.5 on a Core2Duo CPU based system, the -following statistics were measured: +For building LFS, the gain of building on a 64-bit system +compared to a 32-bit system is minimal. +For example, in a test build of LFS-9.1 on a Core i7-4790 CPU based system, +using 4 cores, the following statistics were measured: Architecture Build Time Build Size -32-bit 198.5 minutes 648 MB -64-bit 190.6 minutes 709 MB +32-bit 239.9 minutes 3.6 GB +64-bit 233.2 minutes 4.4 GB -As you can see, the 64-bit build is only 4% faster and is 9% larger than -the 32-bit build. The gain from going to a 64-bit system is relatively -minimal. Of course, if you have more than 4GB of RAM or want to manipulate -data that exceeds 4GB, the advantages of a 64-bit system are substantial. +As you can see, on the same hardware, the 64-bit build is only 3% faster +and is 22% larger than the 32-bit build. If you plan to use LFS as a LAMP +server, or a firewall, a 32-bit CPU may be largely sufficient. On the other +hand, several packages in BLFS now need more that 4GB of RAM to be built +and/or to run, so that if you plan to use LFS as a desktop, the LFS authors +recommend building on a 64-bit system. -The above discussion is only appropriate when comparing -builds on the same hardware. Modern 64-bit systems are considerably -faster than older 64-bit systems and the LFS authors recommend building -on a 64-bit system when given a choice. - -The default 64-bit build that results from LFS is considered a "pure" -64-bit system. That is, it supports 64-bit executables only. Building a -"multi-lib" system requires compiling many applications twice, once for a -32-bit system and once for a 64-bit system. This is not directly supported in -LFS because it would interfere with the educational objective of providing the -instructions needed for a straightforward base Linux system. You can refer to -the Cross Linux From Scratch -project for this advanced topic. - - +The default 64-bit build that results from LFS is considered a +pure 64-bit system. That is, it supports 64-bit executables +only. Building a multi-lib system requires compiling many +applications twice, once for a 32-bit system and once for a 64-bit system. +This is not directly supported in LFS because it would interfere with the +educational objective of providing the instructions needed for a +straightforward base Linux system. Some LFS/BLFS editors maintain a fork +of LFS for multilib, which is accessible at . But it +is an advanced topic. - diff --git a/prologue/preface.xml b/prologue/preface.xml index 21317757f..e940116e1 100644 --- a/prologue/preface.xml +++ b/prologue/preface.xml @@ -14,9 +14,9 @@ + -