bug#15570: 24.3.50; Null pointer crash in (ns-convert-utf8-nfd-to-nfc "\377")

[Carsten Bormann]

(ns-convert-utf8-nfd-to-nfc "\377")

crashes in strlen (called from build_string), 
as it is run on a null-pointer (apparently returned from [utfStr UTF8String]).

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x0000000000000000
0x00007fff94ac3670 in strlen ()
(gdb) where
#0  0x00007fff94ac3670 in strlen ()
#1  0x000000010009fbb4 in build_string ()
#2  0x000000010019300d in Fns_convert_utf8_nfd_to_nfc ()
...
0x00007fff94ac3670 <strlen+16>: pcmpeqb (%rdi),%xmm0
...
(gdb) info reg
rdi            0x0      0

Further, there are no tests for this function.

(Bug manifests itself with tramp no longer working on hosts stuck in 
Latin-1-land, which might be due to an unrelated change.)

Grüße, Carsten


In GNU Emacs 24.3.50.1 (x86_64-apple-darwin, NS apple-appkit-1038.36)
 of 2013-10-06 on bob.porkrind.org
Bzr revision: 114537 dgutov@yandex.ru-20131006012151-wprswhei2ipqvr0c
Windowing system distributor `Apple', version 10.3.1187
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