bash-2.05b and --without-bash-malloc

Matt Reppert arashi at yomerashi.yi.org
Mon May 12 06:39:03 PDT 2003


On Mon, 12 May 2003 12:14:29 +0100
Ian Molton <spyro at f2s.com> wrote:

> On Sun, 11 May 2003 22:59:35 +0000 (UTC)
> gschafer at zip.com.au (Greg Schafer) wrote:
> 
> > Anyone running a bash-2.05b configured with
> > --without-bash-malloc is running a suboptimal shell.
> 
> OOI, what does it do? is it some kind of super fast malloc or soething?

INSTALL says:

`--with-bash-malloc'
     Use the Bash version of `malloc' in `lib/malloc/malloc.c'.  This
     is not the same `malloc' that appears in GNU libc, but an older
     version derived from the 4.2 BSD `malloc'.  This `malloc' is very
     fast, but wastes some space on each allocation.  This option is
     enabled by default.  The `NOTES' file contains a list of systems
     for which this should be turned off, and `configure' disables this
     option automatically for a number of systems.

Correspondingly, NOTES has:
1. configure --without-gnu-malloc on:

        alpha running OSF/1, Linux, or NetBSD (malloc needs 8-byte alignment;
        bash malloc has 8-byte alignment now, but I have no alphas to test on)

        next running NeXT/OS

        all machines running SunOS YP code: SunOS4, SunOS5, HP/UX, if you
        have problems with username completion or tilde expansion for
        usernames found via YP/NIS

        linux (optional, but don't do it if you're using Doug Lea's malloc)

        QNX 4.2
        other OSF/1 machines (KSR/1, HP, IBM AIX/ESA)
        AIX
        sparc SVR4, SVR4.2 (ICL reference port)
        DG/UX
        Cray

        NetBSD/sparc (malloc needs 8-byte alignment; bash malloc has 8-byte
        alignment now, but I have no NetBSD machines to test on)

        BSD/OS 2.1, 3.x if you want to use loadable builtins

        Motorola m68k machines running System V.3.  There is a file descriptor
        leak caused by using the bash malloc because closedir(3) needs to read
        freed memory to find the file descriptor to close

--with-gnu-malloc is the same as --with-bash-malloc (configure told me so!).
That "linux (optional ... " line seems nice and cryptic to me, no? By the way,
recent glibc 2.3 uses Wolfram Gloger's malloc, which he says on the webpage
http://www.malloc.de/en/ is based on Doug Lea's malloc. glibc's malloc.c says
"This is a version (aka ptmalloc2) of malloc/free/realloc written by Doug Lea
and adapted to multiple threads/arenas by Wolfram Gloger." 

So ... we're using Doug Lea's malloc, it *looks* like bash documentation is
telling us "don't configure --without-bash-malloc". (I wonder why. Greg?)

Matt
-- 
Unsubscribe: send email to listar at linuxfromscratch.org
and put 'unsubscribe lfs-dev' in the subject header of the message



More information about the lfs-dev mailing list