pgsql: Fix use of offsetof()

Fix use of offsetof()

Using offsetof() with a run-time computed argument is not allowed in
either C or C++.  Apparently, gcc allows it, but g++ doesn't.

Reviewed-by: Heikki Linnakangas 
Reviewed-by: Thomas Munro 

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f1a469c9f1cfeab9f9c7d4a5d3e75892e7b6f60c

Modified Files
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contrib/bloom/blutils.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)