pgsql: Put in some more safeguards against executing a division-by-zero

Put in some more safeguards against executing a division-by-zero.

Add dummy returns before every potential division-by-zero in int8.c,
because apparently further "improvements" in gcc's optimizer have
enabled it to break functions that weren't broken before.

Aurelien Jarno, via Martin Pitt

Branch
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REL8_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/24aad03e98a7e38614100457defdedf75c473bc4

Modified Files
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src/backend/utils/adt/int8.c |   19 +++++++++++++++++++
1 files changed, 19 insertions(+), 0 deletions(-)