[Clfs-support] Please Explain {BUILD{32, 64}} in Ch. {7, 8} with `chroot`

[Dan McGhee]

Using SVN-20090907-Native-Multilib

At the outset, I am compiler illiterate.  I can follow directions well, 
but I also like to have at least a rudimentary understanding of the 
commands I am using. In Ch. 6 the method for specifiying which "bit 
build" to use is generally `CC="${CC} ${BUILD{32,64}}"`.  My 
understanding is that {CC} is the C compiler, gcc.  In Chapters 7 & 8, 
this is done, apparently using `"gcc {BUILD{32,64}}"`.

My question comes from "chrooting" with a "clean" environment.  How does 
gcc know, in this environment, to use -m32 or -m34.  The .bashrc files 
in Ch. 6 were valid only for user clfs when `su - clfs` from root.  
However, this file does not exist in `chroot xxx.`  Would someone please 
explain this.

This is not a question about how the book is written.  It's a question 
that I'm too lazy to completely research--cause I wanna get my CLFS built.

Thanks,

Dan