bms_prev_member mistakenly has a hardcoded 24 in the function. This
should really be BITS_PER_BITMAPWORD - 8 so that it is properly set to
56 if someone compiles with 64-bit bitmapwords.
The attached fixes this and also adds a test to exercise the function
a bit. [1] indicates there's currently no coverage of this function at
all.
[1] https://coverage.postgresql.org/src/backend/nodes/bitmapset.c.gcov.html
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David Rowley http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services