tower-test: Use memmove(), not memcpy(), for overlapping memory move.
[pspp] / tests / output /
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-rw-r--r-- 11243 ascii.at
-rw-r--r-- 2625 charts.at
-rw-r--r-- 766 output.at
-rw-r--r-- 947 paper-size.at
-rw-r--r-- 9555 render-test.c
-rw-r--r-- 33945 render.at