Hi Luisa
I'm no expert in OSGEO4W but I believe you should
1- shut down Msys and reboot the PC
2- Try again
I believe that you might have 1 problem: You don't have an include folder. I don't know how can you add it to your GRASS installation by using OSGEO4W. But that is not one of the steps in that compiling for MS-WIndows.
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