Segmentation fault on concat

anonamonk has asked for the wisdom of the Perl Monks concerning the following question:

is there anything obvious about this code which would cause a segmentation fault?

 my $style_file = $$config{'dir'}."/";
    $style_file .= 'main/'.$$config{'style'}.".xsl";
[download]

$$conf{'dir'} and $conf{'style'} are initialized and concatenated without a problem; the error occurs when I add remove the '/' after 'main'

Hoping for a fresh set of eyes. Thanks...

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Re: Segmentation fault on concat by dave_the_m (Monsignor) on Nov 18, 2004 at 01:06 UTC
Perl should never segfault(). If you can reduce it to a small standalone program that exhibits the segfault, and if it still segfaults using 5.8.5, then report it using perlbug. Dave. () ignoring of course: deeply recursive regexes, foreach loops that modify the loop array, functions that delete variables used by the caller in the arglist, anything involving /(?{...})/, and of course anything with the slightest whiff of XS.	[reply]
Re^2: Segmentation fault on concat by pg (Canon) on Nov 18, 2004 at 02:22 UTC
"Perl should never segfault(). " Why ;-? It might make sense to say that it is not really up to the OP to cause seg fault, unless he is directly doing some c code through Perl. But Perl seg faults, as what inside is c, and c seg faults. Does't matter whether his code is bad or good. If Perl seg faults when run his code, it is still a bug in Perl. Update:* After read gaal's reply, and also some private chat with her, I think that I might have misunderstood dave_the_m's intention, and actually he meant the same thing as what I put in my reply.	[reply]
Re^3: Segmentation fault on concat by gaal (Parson) on Nov 18, 2004 at 04:50 UTC
I believe dave_the_m meant that perl isn't supposed to segfault, and that if it does it's a bug in perl -- not to claim the OP was lying :)	[reply]
Re^4: Segmentation fault on concat by dave_the_m (Monsignor) on Nov 18, 2004 at 11:36 UTC
Re^2: Segmentation fault on concat by Cody Pendant (Prior) on Nov 18, 2004 at 03:01 UTC
`anything involving /(?{...})/` Care to elaborate on that? I don't know what problem you're referring to. ($_='kkvvttuubbooppuuiiffssqqffssmmiibbddllffss') =~y~b-v~a-z~s; print	[reply] [d/l]
Re^3: Segmentation fault on concat by dave_the_m (Monsignor) on Nov 18, 2004 at 11:40 UTC
Care to elaborate on that? I don't know what problem you're referring to I can't remember the exact details off the top of my head, but I seem to remember that trying to clone an anon sub within an re_eval is bad news. I'm currently in the process of rewriting the (?{...}) implementation for 5.10.0 to avoid such problems. Dave.	[reply]
Re: Segmentation fault on concat by graff (Chancellor) on Nov 18, 2004 at 01:44 UTC
I'm all for dave_the_m's advice to try demonstrating the bad behavior in a minimal script. This often leads to finding a bug that you weren't looking for previously. But apart from that, I'm wondering why you wouldn't do your string assignment some other (possibly simpler) way, such as: `my $style_file = sprintf "%s/main/%s.xsl", $$config{dir}, $$config{sty +le};` [download] or maybe: `my $style_file = join "/", $$config{dir}, 'main', "$$config{style}.xsl +";` [download]	[reply] [d/l] [select]