CMake 2.6.0 cross-compile: 1st time failed, 2nd time passed

Hi List,

I am here trying to cross-compile a tiny demo project
with cmake 2.6.0.

When I ran cmake for the first time, link failed because
CMAKE_C_FLAGS was not used to compile cmTryCompileExec.
Then I modified nothing, but only ran cmake again.
CMAKE_C_FLAGS was used properly and link passed.

The project settings and logs are attached below.
Could you point out which part I have done wrong and
how to fix it.
Thanks in advance.

Best regards.
ning

=====project setting=====
-----dir structure-----
.
|-- CMakeLists.txt
|-- build/
|-- cross-tools.cmake
`-- tiny.c

-----tiny.c-----
#include <stdio.h>
int main()
{