bug#15075: 24.3.50; Infinite loop when closing some connections

[Lars Magne Ingebrigtsen <larsi@gnus.org>]

Hey, that was fast.

This bug isn't reliably repeatable, so it may be timing-related or
something.  But here's an -O0 build:

0  0x00007ffff2f4718d in read () from /lib/x86_64-linux-gnu/libpthread.so.0
#1  0x0000000000536ea3 in emacs_read (fildes=21, buf=0x7fffffff8830 "221 hermes.netfonds.no closing connection\r\n", nbyte=4096)
    at sysdep.c:2300
#2  0x00000000005f88c5 in read_process_output (proc=71750957, channel=21) at process.c:4980
#3  0x00000000005f71c3 in wait_reading_process_output (time_limit=0, nsecs=-1, read_kbd=0, do_display=false, wait_for_cell=12567106, 
    wait_proc=0x446d528, just_wait_proc=0) at process.c:4435
#4  0x00000000005f5f7f in Faccept_process_output (process=71750957, seconds=12567106, millisec=12567106, just_this_one=12567106)
    at process.c:3948
#5  0x00000000005abeea in Ffuncall (nargs=2, args=0x7fffffff9da8) at eval.c:2864
#6  0x00000000005ebce6 in exec_byte_code (bytestr=70546449, vector=72148261, maxdepth=20, args_template=12567106, nargs=0, args=0x0)
    at bytecode.c:905
#7  0x00000000005eb185 in Fbyte_code (bytestr=70546449, vector=72148261, maxdepth=20) at bytecode.c:478
#8  0x00000000005aaa4a in eval_sub (form=72367398) at eval.c:2229
#9  0x00000000005a8722 in internal_catch (tag=16167106, func=0x5aa416 <eval_sub>, arg=72367398) at eval.c:1113
#10 0x00000000005ecad6 in exec_byte_code (bytestr=68666769, vector=72148485, maxdepth=20, args_template=12567106, nargs=0, args=0x0)
    at bytecode.c:1086
#11 0x00000000005ac857 in funcall_lambda (fun=72148573, nargs=1, arg_vector=0x44ce605) at eval.c:3087
#12 0x00000000005ac04c in Ffuncall (nargs=2, args=0x7fffffffa8f8) at eval.c:2902
#13 0x00000000005ebce6 in exec_byte_code (bytestr=75448801, vector=72146685, maxdepth=12, args_template=12567106, nargs=0, args=0x0)
    at bytecode.c:905
#14 0x00000000005eb185 in Fbyte_code (bytestr=75448801, vector=72146685, maxdepth=12) at bytecode.c:478
#15 0x00000000005aaa4a in eval_sub (form=72371078) at eval.c:2229
#16 0x00000000005a74ce in Fprogn (body=72369206) at eval.c:460
#17 0x00000000005a750c in unwind_body (body=72369206) at eval.c:474

-- 
(domestic pets only, the antidote for overdose, milk.)
  No Gnus T-Shirt for sale: http://ingebrigtsen.no/no.php
  and http://lars.ingebrigtsen.no/2013/08/twenty-years-of-september.html