Require binutils 2.20 or later to build glibc

[Joseph S. Myers]

On Mon, 27 Feb 2012, Ryan Arnold wrote:

> I have a concern with making 4.3 the minimum compiler.  There are still
> current and previous versions of GNU/Linux Distributions that have
> earlier-than-4.3 compilers.
> 
> I maintain a toolchain that is built on n-1 distributions to work there
> and at level n.  Making 4.3 the minimum compiler complicates the initial
> bootstrap process (by introducing several extra stages).

A toolchain including glibc?

Normally a native toolchain would not include glibc - it would work with 
the system's pre-existing glibc, since using a different glibc from that 
installed in /lib etc. isn't particularly convenient - while a cross 
toolchain would include the compiler used to build glibc and the 
distribution's native compiler version wouldn't be relevant.  (To be 
clear, the version requirement proposal is purely about $CC, the compiler 
used to build glibc itself, not $BUILD_CC, the native compiler for the 
system on which glibc is built.)

For the past couple of months it seems at least 4.4 has actually been 
required - and noone noticed until recently - because of the uchar.h 
issue.  While GCC 4.3 was maintained until last summer, I closed 4.2 
branch in March 2009 (and 4.1 in July 2008).

-- 
Joseph S. Myers
joseph@codesourcery.com