[LLVMdev] llvm-ranlib: Bus Error in regressions + fix

[Evan Jones]

On Nov 22, 2005, at 19:10, Reid Spencer wrote:
> 1. What is the path name associated with TmpArchive? If its the same 
> as the path name associated with archPath then that's a bug, probably 
> introduced when Path::makeUnique is called from 
> Path::createTemporaryFileOnDisk which is called from line 377 of 
> ArchiveWriter.cpp.

This does not appear to be the problem. I excluded the lines from the 
strace that created this temporary file. After line 377:

(gdb) p TmpArchive
$2 = {path = {static npos = 4294967295,
     _M_dataplus = {<allocator<char>> = {<No data fields>},
       _M_p = 0x835407c "temp.GNU.a-PozKFJ"}, static 
_S_empty_rep_storage = {0,
       0, 4, 0}}}
(gdb) p archPath
$3 = {path = {static npos = 4294967295,
     _M_dataplus = {<allocator<char>> = {<No data fields>},
       _M_p = 0x83545f4 "temp.GNU.a5\b"}, static _S_empty_rep_storage = 
{0, 0,
       4, 0}}}

So these two variables are pointing to different files, and the 
creation of TmpArchive works just fine.  The strace including the parts 
that reference the temporary file is appended to the end of the email. 
The very last open to the "archPath" file is at line 429, where it 
truncates it even though the foreignST pointer refers to data mmaped in 
that file. Is this data supposed to be copied out of the original file, 
or is another temporary supposed to be created and then the original 
could be replaced using a file move operation instead?

I'll try this on my Debian unstable system tomorrow. If ranlib works 
there, maybe I can track down the difference.

Evan Jones


open("temp.GNU.a", O_RDONLY)            = 3
fstat64(3, {st_mode=S_IFREG|0600, st_size=4210, ...}) = 0
mmap2(NULL, 8192, PROT_READ, MAP_PRIVATE, 3, 0) = 0x40017000
gettimeofday({1132714484, 283020}, NULL) = 0
getpid()                                = 28656
open("temp.GNU.a-O1Q6E8", O_RDWR|O_CREAT|O_EXCL, 0600) = 4
close(4)                                = 0
open("temp.GNU.a-O1Q6E8", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 4
close(4)                                = 0

*** SIGNAL HANDLING REMOVED ***

open("temp.GNU.a-O1Q6E8", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 4
brk(0)                                  = 0x8357000
brk(0x8359000)                          = 0x8359000
fstat64(4, {st_mode=S_IFREG|0600, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 
0) = 0x40019000
_llseek(4, 0, [0], SEEK_CUR)            = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
brk(0)                                  = 0x8359000
brk(0x8369000)                          = 0x8369000
brk(0)                                  = 0x8369000
brk(0x836a000)                          = 0x836a000
mmap2(NULL, 2002944, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 
-1, 0) = 0x4013b000
munmap(0x4013b000, 2002944)             = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
_llseek(4, 0, [0], SEEK_SET)            = 0
write(4, "!<arch>\nevenlen/        11008330"..., 4040) = 4040
close(4)                                = 0
munmap(0x40019000, 4096)                = 0
access("temp.GNU.a-O1Q6E8", F_OK)       = 0
open("temp.GNU.a-O1Q6E8", O_RDONLY)     = 4
fstat64(4, {st_mode=S_IFREG|0600, st_size=4040, ...}) = 0
mmap2(NULL, 4096, PROT_READ, MAP_PRIVATE, 4, 0) = 0x40019000
open("temp.GNU.a", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 5
fstat64(5, {st_mode=S_IFREG|0600, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 
0) = 0x4001a000
_llseek(5, 0, [0], SEEK_CUR)            = 0
--- SIGBUS (Bus error) @ 0 (0) ---


--
Evan Jones
http://evanjones.ca/