gnu/77818: GDB locks in wait4() when running applications

[Seán C. Farley]

I finally compiled Zsh with debugging and got the following trace.  I
ran it by the following line:
LD_LIBRARY_PATH=/tmp/libc SHELL=/bin/sh gdb /usr/local/bin/zsh

Program received signal SIGINT, Interrupt.
0x281a9efb in sigsuspend () from /lib/libc.so.5
(gdb) where
#0  0x281a9cfb in sigsuspend () at sigsuspend.S:2
#1  0x280e07dc in signal_suspend (sig=20, sig2=2) at signals.c:367
#2  0x280b92e8 in waitforpid (pid=11195) at jobs.c:1120
#3  0x280a3dda in getoutput (cmd=0x8060e5c "uname -s", qt=1) at exec.c:2869
#4  0x280e2a0c in stringsubst (list=0xbfbfe7c0, node=0xbfbfe7d0, ssub=4,
     asssub=0) at subst.c:189
#5  0x280e2378 in prefork (list=0xbfbfe7c0, flags=6) at subst.c:74
#6  0x280a0886 in addvars (state=0xbfbfe880, pc=0xbfbfe7c0, export=0)
     at exec.c:1614
#7  0x2809ec5d in execsimple (state=0x1) at exec.c:802
#8  0x2809edb7 in execlist (state=0xbfbfe880, dont_change_job=0, exiting=0)
     at exec.c:855
#9  0x2809eb9a in execode (p=0x80608e0, dont_change_job=0, exiting=0)
     at exec.c:775
#10 0x280b3a8a in loop (toplevel=0, justonce=0) at init.c:165
#11 0x280b58b8 in source (s=0xbfbfe950 "/root/.zshenv") at init.c:1043
#12 0x280b5b1c in sourcehome (s=0x280f458d ".zshenv") at init.c:1088
#13 0x280b54e7 in run_init_scripts () at init.c:937
#14 0x280b63da in zsh_main (argc=1, argv=0xbfbfeac0) at init.c:1262
#15 0x08048583 in main (argc=1, argv=0xbfbfeac0) at ./main.c:93

I hope this can help find the problem.

Seán
-- 
sean-freebsd at farley.org