patchTest for failing pread() on cygwin.

diff --git a/t/t5610-clone-fail.sh b/t/t5610-clone-fail.sh
new file mode 100755
index 0000000..d30b25e
--- /dev/null
+++ b/t/t5610-clone-fail.sh
@@ -0,0 +1,29 @@
+#!/bin/sh
+#
+# Copyright (C) 2007 Stefan-W. Hahn <stefan.hahn@s-hahn.de>
+#
+
+test_description='test git-clone failure on cygwin using pread()
+
+This test covers the fact that git-clone fails, if pread() does not
+work properly, because the size of objects makes it neccessary to
+read data from a not zero offset.'
+
+. ./test-lib.sh
+
+# Need a repo to clone
+test_create_repo foo2
+
+GIT_AUTHOR_EMAIL=xxxxxxxx@yyyyyyyy.yyyyy.yyyyyyy.yyy
+GIT_COMMITTER_EMAIL=xxxxxxxx@yyyyyyyy.yyyyy.yyyyyyy.yyy
+export GIT_AUTHOR_EMAIL
+export GIT_COMMITTER_EMAIL
+
+(cd foo2 && echo "Hello" > file && git add file && git commit -m 'add file' >/dev/null 2>&1)
+(cd foo2 && echo "Hello2" >> file && git commit -a -m 'test' >/dev/null 2>&1)
+
+test_expect_success \
+    'clone with resolving' \
+    'git-clone foo2 bar2'
+
+test_done

Makefile, compat/pread.c, git-compat-util.h

diff --git a/Makefile b/Makefile
index 6c12bc6..47af0de 100644
--- a/Makefile
+++ b/Makefile
@@ -69,6 +69,9 @@ all:
 #
 # Define NO_MMAP if you want to avoid mmap.
 #
+# Define NO_PREAD if you have a problem with pread() system call (i.e.
+# cygwin.dll before v1.5.22).
+#
 # Define NO_FAST_WORKING_DIRECTORY if accessing objects in pack files is
 # generally faster on your platform than accessing the working directory.
 #
@@ -523,6 +526,10 @@ ifdef NO_MMAP
 	COMPAT_CFLAGS += -DNO_MMAP
 	COMPAT_OBJS += compat/mmap.o
 endif
+ifdef NO_PREAD
+	COMPAT_CFLAGS += -DNO_PREAD
+	COMPAT_OBJS += compat/pread.o
+endif
 ifdef NO_FAST_WORKING_DIRECTORY
 	BASIC_CFLAGS += -DNO_FAST_WORKING_DIRECTORY
 endif
diff --git a/compat/pread.c b/compat/pread.c
new file mode 100644
index 0000000..cd1da87
--- /dev/null
+++ b/compat/pread.c
@@ -0,0 +1,15 @@
+#include "../git-compat-util.h"
+
+ssize_t git_pread(int fd,void *buf,size_t count,off_t offset)
+{
+        off_t current_offset = lseek(fd, 0, SEEK_CUR);
+
+        if (lseek(fd, offset, SEEK_SET) < 0)
+                return EINVAL;
+
+        ssize_t rc=xread(fd, buf, count);
+
+        if (current_offset != lseek(fd, current_offset, SEEK_SET))
+                return EINVAL;
+        return rc;
+}
diff --git a/git-compat-util.h b/git-compat-util.h
index e023bf1..00b14df 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -107,6 +107,11 @@ extern int git_munmap(void *start, size_t length);
 #define DEFAULT_PACKED_GIT_LIMIT \
 	((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))
 
+#ifdef NO_PREAD
+#define pread git_pread
+extern ssize_t git_pread(int fd,void *buf,size_t count,off_t offset);
+#endif
+
 #ifdef NO_SETENV
 #define setenv gitsetenv
 extern int gitsetenv(const char *, const char *, int);