Re: Bug with -o posix, local variables and assignment preceding builtins
On Mon, 2010-02-08 at 17:38 -0500, Chet Ramey wrote:
> On 2/7/10 8:33 PM, Crestez Dan Leonard wrote:
> > We encountered a strange bug while working on bash-completion. I was
> > originally only able to reproduce this through a fairly elaborate setup
> > but Freddy Vulto found a tiny test case:
> >
> > set -o posix
> > t() {
> > local x
> > BAR=a eval true
> > }
> > BAR=b; t; echo $BAR
> >
> > Bash documentation claims the following (section 6.11 point 23):
>
> See if the attached patch does the trick.
>
> Chet
Yes, it now works correctly. I tested both the simple example above and
my initial testing setup.
Re: Bug with -o posix, local variables and assignment preceding builtins
On 2/7/10 8:33 PM, Crestez Dan Leonard wrote:
> We encountered a strange bug while working on bash-completion. I was
> originally only able to reproduce this through a fairly elaborate setup
> but Freddy Vulto found a tiny test case:
>
> set -o posix
> t() {
> local x
> BAR=a eval true
> }
> BAR=b; t; echo $BAR
>
> Bash documentation claims the following (section 6.11 point 23):
See if the attached patch does the trick.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRUc...@case.eduhttp://cnswww.cns.cwru.edu/~chet/
*** ../bash-4.1-patched/variables.c 2009-11-03 14:13:58.0 -0500
--- variables.c 2010-02-08 17:36:18.0 -0500
***
*** 3809,3812
--- 3809,3817
if (tempvar_p (var) && (posixly_correct || (var->attributes &
att_propagate)))
{
+ /* Make sure we have a hash table to store the variable in while it is
+being propagated down to the global variables table. Create one if
+we have to */
+ if ((vc_isfuncenv (shell_variables) || vc_istempenv (shell_variables))
&& shell_variables->table == 0)
+ shell_variables->table = hash_create (0);
/* XXX - should we set v->context here? */
v = bind_variable_internal (var->name, value_cell (var),
shell_variables->table, 0, 0);
Re: Bug with -o posix, local variables and assignment preceding builtins
On Feb 7, 7:33 pm, Crestez Dan Leonard wrote:
> We encountered a strange bug while working on bash-completion. I was
> originally only able to reproduce this through a fairly elaborate setup
> but Freddy Vulto found a tiny test case:
>
> set -o posix
> t() {
> local x
> BAR=a eval true
> }
> BAR=b; t; echo $BAR
>
> Bash documentation claims the following (section 6.11 point 23):
>
> """ Assignment statements preceding posix special builtins persist in
> the shell environment after the builtin completes."""
>
> The above example should always print "a" but with "#local x" commented
> it prints "b". This is obviously wrong; the x variable is not even used.
>
> This can be reproduced on all versions of bash since at least bash-3.0
> (probably on bash-2 as well). I also checked Debian's dash as an
> alternative posix-compliant shell and it always prints "a" as expected.
For reference, ksh93, busybox ash and zsh (with setopt posixbuiltins)
print "a"
Bug with -o posix, local variables and assignment preceding builtins
We encountered a strange bug while working on bash-completion. I was
originally only able to reproduce this through a fairly elaborate setup
but Freddy Vulto found a tiny test case:
set -o posix
t() {
local x
BAR=a eval true
}
BAR=b; t; echo $BAR
Bash documentation claims the following (section 6.11 point 23):
""" Assignment statements preceding posix special builtins persist in
the shell environment after the builtin completes."""
The above example should always print "a" but with "#local x" commented
it prints "b". This is obviously wrong; the x variable is not even used.
This can be reproduced on all versions of bash since at least bash-3.0
(probably on bash-2 as well). I also checked Debian's dash as an
alternative posix-compliant shell and it always prints "a" as expected.
