pgsql: Fix numeric_power() when the exponent is INT_MIN. - Mailing list pgsql-committers

From Dean Rasheed
Subject pgsql: Fix numeric_power() when the exponent is INT_MIN.
Date
Msg-id E1kwkNN-0007LT-VA@gemulon.postgresql.org
Whole thread Raw
List pgsql-committers
Fix numeric_power() when the exponent is INT_MIN.

In power_var_int(), the computation of the number of significant
digits to use in the computation used log(Abs(exp)), which isn't safe
because Abs(exp) returns INT_MIN when exp is INT_MIN. Use fabs()
instead of Abs(), so that the exponent is cast to a double before the
absolute value is taken.

Back-patch to 9.6, where this was introduced (by 7d9a4737c2).

Discussion: https://postgr.es/m/CAEZATCVd6pMkz=BrZEgBKyqqJrt2xghr=fNc8+Z=5xC6cgWrWA@mail.gmail.com

Branch
------
REL_12_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/258b7700551c4fc01ecd55d7ead4085184d4dce3

Modified Files
--------------
src/backend/utils/adt/numeric.c       | 2 +-
src/test/regress/expected/numeric.out | 6 ++++++
src/test/regress/sql/numeric.sql      | 1 +
3 files changed, 8 insertions(+), 1 deletion(-)


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