[Bug build/16370] New: building gcc fails when bash is not installed

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

Bug ID: 16370
Summary: building gcc fails when bash is not installed
Product: gdb
Version: 7.6
Status: NEW
Severity: critical
Priority: P2
Component: build
Assignee: unassigned at sourceware dot org
Reporter: maillist-gdb at barfooze dot de

when bash is installed, configure will always prefer and use bash, so in order
to reproduce one has to temporarily uninstall, remove or rename his bash
binary.

when /bin/sh is busybox' ash, the following error breaks the build:

gdb-7.6.2/opcodes/configure: .: line 12678: can't open
'../../opcodes/configure.host'

inserting debug code into bfd/configure shows that it's actually bfd/configure
that is running, instead of opcodes/configure (as displayed):

bfd/configure
+ echo XXX ${srcdir}/configure.host XXX > /dev/tty
# Permit host specific settings.
. ${srcdir}/configure.host

displays:
XXX ../../opcodes/configure.host XXX
gdb-7.6.2/opcodes/configure: .: line 12680: can't open
'../../opcodes/configure.host'

with debian's dash as /bin/sh, one gets the following error:

gdb-7.6.2/opcodes/configure: 3235: ./configure.lineno: Syntax error: "fi"
unexpected

both dash and busybox ash are strictly posix conformant sh implementations,
and work fine for all other packages including binutils 2.24.

to me it looks like there happened some typo somewhere, and the syntax error is
not detected/properly handled by bash (so it works by chance), or some bashism
crept into the build at some point, without being noticed as bash is even in
debians baseinstall.

this error did not happen with gdb 7.4. the commit that introduced the bug can
probably quickly be found using a git bisect on a box that has /bin/bash
symlinked to /bin/dash


the configure line used to build gdb was:
LDFLAGS="-static" \
CFLAGS="-D_GNU_SOURCE -D_LARGEFILE64_SOURCE -O0" \
../configure -C \
--prefix= --disable-werror --disable-tls --with-system-zlib=yes \
--enable-64-bit-bfd
--enable-targets=x86_64-linux,i386-linux,powerpc-linux,arm-linux,mips-linux,mipsel-linux,microblaze-linux
\
--disable-sim --disable-tui

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

maillist-gdb at barfooze dot de changed:

What |Removed |Added
----------------------------------------------------------------------------
Summary|building gcc fails when |building gdb fails when
|bash is not installed |bash is not installed

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #1 from maillist-gdb at barfooze dot de ---
update: 7.5.1 is the latest version that works with dash symlinked to /bin/bash
and /bin/sh.
7.6(.0) is the first version that fails.

[sergiodj at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

Sergio Durigan Junior <sergiodj at redhat dot com> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |sergiodj at redhat dot com

--- Comment #2 from Sergio Durigan Junior <sergiodj at redhat dot com> ---
Thanks for the bug report.

I'm not able to reproduce this. I am using Fedora 19 here, and did what you
recommended (installed dash, symlinked bash -> dash, sh -> dash), but configure
runs fine for me on both git HEAD and the 7.6 .tar.bz2.

BTW, do you see this bug using git HEAD?

[sergiodj at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

Sergio Durigan Junior <sergiodj at redhat dot com> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |WAITING

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #3 from maillist-gdb at barfooze dot de ---
the same happens for binutils 2.24. there must've been some bashism that crept
into the configure (config.sub/.guess/.host etc) infrastructure during the last
year.

sorry i didn't have time yet to experiment with latest git :/

[sergiodj at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #4 from Sergio Durigan Junior <sergiodj at redhat dot com> ---
It would be very useful if you could identify which kind of "bashism" you're
talking about. As I said, I could not reproduce the bug, so there is nothing I
can do to fix it. I will wait a few more weeks until you provide more input.

[ncopa at alpinelinux dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #8 from ncopa at alpinelinux dot org ---
This change/revert appears to fix it:

-BFD_VERSION=`${srcdir}/../bfd/configure --version | sed -n -e '1s,.* ,,p'`
+BFD_VERSION=`sed -n 's/AC_INIT(\[bfd\], *\[\([0-9.]*\)\])/\1/p'
<${srcdir}/../bfd/configure.in`

[ncopa at alpinelinux dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #7 from ncopa at alpinelinux dot org ---
I finally found a way to reproduce it on fedora-20 and binutils-2.24:

yum install busybox
mv /bin/sh /bin/sh.backup
ln -s /usr/sbin/busybox /bin/sh
CONFIG_SHELL=/bin/sh ./configure
make configure-host

Some things to note:

CONFIG_SHELL=/bin/ash ./configure does not trigger it.

This is from configure.lineno:
...
for as_base in sh bash ksh sh5; do
# Try only shells that exist, to save several forks.
as_shell=$as_dir/$as_base
...

note that it does not check for "ash".

configure will find and use /bin/bash if it exists - even if /bin/sh points to
something else. So rename /bin/bash might also trigger it (careful though.. its
the shell for root so you can easily brick your fedora box...)

I was not able to trigger it with dash. I think this is becuase recent versions
of dash has support for $LINENO, so it does not use sed to generate
configure.lineno (where i think the problem is). (see under LINENO on
http://www.gnu.org/software/autoconf/manual/autoconf.html#Special-Shell-Variables)

I think it might be possible to trigger it with dash on (older?) debian.
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=582952

My conclusion is that something is broke with the generation of
configure.lineno in the version of autoconf that created the tarball. (2.64).

[ncopa at alpinelinux dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #6 from ncopa at alpinelinux dot org ---
After more digging in the generated autoconf, it seems that there is something
wrong with the generated configure.lineno. If I regenerate configure scripts
with autoconf 2.69 it all works again.

My guess is that the version of autoconf used to generate the tarballs is
buggy.

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #9 from maillist-gdb at barfooze dot de ---
ncopa, thanks for your findings.
i can confirm that this patch
http://git.proteanos.com/pkg/gdb.git/tree/patches/02_fix-opcodes-configure-bfd-version-on-busybox-ash.patch
fixes the issue in gdb 7.6.2.
i wonder if the new sed command in that line is not ERE conforming.

[ncopa at alpinelinux dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #10 from ncopa at alpinelinux dot org ---
(In reply to maillist-gdb from comment #9)

Post by maillist-gdb at barfooze dot de
i wonder if the new sed command in that line is not ERE conforming.

I doubt that. I think its a bug in autoconf and I think this fixes it:

http://git.savannah.gnu.org/gitweb/?p=autoconf.git;a=commit;h=55f532e539427ff5829790fd71b6f8c6342b141a

Which means that you should not use anything older than autoconf-2.68 to
generate the tarballs.

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

--- Comment #11 from maillist-gdb at barfooze dot de ---
filed https://sourceware.org/bugzilla/show_bug.cgi?id=16948 ( bug #16948 )

[maillist-gdb at barfooze dot de]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

maillist-gdb at barfooze dot de changed:

What |Removed |Added
----------------------------------------------------------------------------
Depends on| |16948

[carlos at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

Carlos O'Donell <carlos at redhat dot com> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |WAITING
Component|core |build
Version|unspecified |7.6
Product|netresolve |gdb

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=16370

Tom Tromey <tromey at sourceware dot org> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|WAITING |RESOLVED
CC| |tromey at sourceware dot org
Resolution|--- |FIXED

--- Comment #12 from Tom Tromey <tromey at sourceware dot org> ---
gdb has recently upgraded to autoconf 2.69, so according to comment #10,
I believe this is fixed.