pgsql: Restore SIGFPE handler after initializing PL/Perl.

Restore SIGFPE handler after initializing PL/Perl.

Perl, for some unaccountable reason, believes it's a good idea to reset
SIGFPE handling to SIG_IGN.  Which wouldn't be a good idea even if it
worked; but on some platforms (Linux at least) it doesn't work at all,
instead resulting in forced process termination if the signal occurs.
Given the lack of other complaints, it seems safe to assume that Perl
never actually provokes SIGFPE and so there is no value in the setting
anyway.  Hence, reset it to our normal handler after initializing Perl.

Report, analysis and patch by Andres Freund.

Branch
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REL8_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/f98d8d59a19ba4b745fb7d4795055540c9725cd6

Modified Files
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src/pl/plperl/plperl.c |   14 ++++++++++++++
1 files changed, 14 insertions(+), 0 deletions(-)