pgsql: foreach() and list_delete() don't mix.

foreach() and list_delete() don't mix.

Fix crash when releasing duplicate entries in the encoding conversion cache
list, caused by releasing the current entry of the list being chased by
foreach().  We have a standard idiom for handling such cases, but this
loop wasn't using it.

This got broken in my recent rewrite of GUC assign hooks.  Not sure how
I missed this when testing the modified code, but I did.  Per report from
Peter.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/88dc6fa7a164c306d8a1295769edb818d8520a3f

Modified Files
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src/backend/utils/mb/mbutils.c |   12 ++++++++++--
1 files changed, 10 insertions(+), 2 deletions(-)