zsh hangs loading init files

[Greg Klanderman <gak@klanderman.net>]

Hi all,

I'm in the process of transitioning my work computer from debian 5.0
(lenny) to an Ubuntu variant that Google uses (Goobuntu) and having
trouble with newer versions of zsh.  While loading my init files, zsh
hangs several times for 10-30 sec.  This is not happening on 4.3.10
which came with the Goobuntu distribution, or a 4.3.10 which I built
from source, but is occurring with 4.3.15 and a cvs checkout in
between 4.3.11 and 4.3.12 which I built.  I do not see the problem on
my old debian box.

By putting in some print statements, the first hang seems to occur
at a command substitution

| case "$(uname -s)" in
|   ...

the last bit of strace up to the hang is:

rt_sigprocmask(SIG_BLOCK, [CHLD], [CHLD], 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [CHLD], [CHLD], 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [CHLD], [CHLD], 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [CHLD], [CHLD], 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [CHLD], [CHLD], 8) = 0
rt_sigaction(SIGINT, {0x476250, [], SA_RESTORER|SA_INTERRUPT, 0x7f883f6c1af0}, NULL, 8) = 0
rt_sigaction(SIGINT, {0x476250, [], SA_RESTORER|SA_INTERRUPT, 0x7f883f6c1af0}, NULL, 8) = 0
rt_sigaction(SIGINT, {0x476250, [], SA_RESTORER|SA_INTERRUPT, 0x7f883f6c1af0}, NULL, 8) = 0
rt_sigaction(SIGINT, {0x476250, [], SA_RESTORER|SA_INTERRUPT, 0x7f883f6c1af0}, NULL, 8) = 0
rt_sigaction(SIGINT, {0x476250, [], SA_RESTORER|SA_INTERRUPT, 0x7f883f6c1af0}, NULL, 8) = 0
rt_sigaction(SIGINT, {0x476250, [], SA_RESTORER|SA_INTERRUPT, 0x7f883f6c1af0}, NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
pipe([3, 4])                            = 0
fcntl(3, F_DUPFD, 10)                   = 13
close(3)                                = 0
fcntl(4, F_DUPFD, 10)                   = 14
close(4)                                = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [CHLD], 8) = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f88402d89d0) = 26368
close(14)                               = 0
fcntl(13, F_GETFL)                      = 0 (flags O_RDONLY)
fstat(13, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f88402de000
lseek(13, 0, SEEK_CUR)                  = -1 ESPIPE (Illegal seek)
read(13, ######## hangs here for 10-30 sec then continues

I suppose at this point I will binary search for the commit that broke
things and go from there, but wanted to put this out in case anyone
has any ideas what it might be.

thanks,
Greg