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Problem with mmap in latest snapshot


My application uses mmap on a 16MB file. On released 1.7.7, there's no problem. But with the 20100919 snapshot, it crashes when it tries to access the mmap space past the first 32KB or so. Attached is a simple test program that illustrates the problem.

***** With 1.7.7 *****

$ uname -a
CYGWIN_NT-6.1-WOW64 hkehoe1 1.7.7(0.230/5/3) 2010-08-31 09:58 i686 Cygwin

$ ./a
creating mmap-test-file
Writing zeros
mmap-ing
writing ones to mmap region
done!

$ ls -l mmap*
-rw-r--r--+ 1 hkehoe Domain Users 16777216 2010-09-20 14:51 mmap-test-file

$ od -tc mmap-test-file
0000000 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001
*
100000000

***** With snapshot *****

$ uname -a
CYGWIN_NT-6.1-WOW64 hkehoe1 1.7.8s(0.231/5/3) 20100919 16:19:37 i686 Cygwin

$ ./a
creating mmap-test-file
Writing zeros
mmap-ing
writing ones to mmap region
Segmentation fault (core dumped)

$ od -tc mmap-test-file
0000000 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001
*
0100000  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0  \0
*
100000000




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Attachment: test.c
Description: Text document

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