pgsql: Fix leak of LLVM "fatal-on-oom" section counter.

Fix leak of LLVM "fatal-on-oom" section counter.

llvm_release_context() called llvm_enter_fatal_on_oom(), but was missing
the corresponding llvm_leave_fatal_on_oom() call. As a result, if JIT was
used at all, we were almost always in the "fatal-on-oom" state.

It only makes a difference if you use an extension written in C++, and
run out of memory in a C++ 'new' call. In that case, you would get a
PostgreSQL FATAL error, instead of the default behavior of throwing a
C++ exception.

Back-patch to all supported versions.

Reviewed-by: Daniel Gustafsson
Discussion: https://www.postgresql.org/message-id/54b78cca-bc84-dad8-4a7e-5b56f764fab5@iki.fi

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/59c2a6fe9b6518255d99a6bbf9006a98a0aefa6b

Modified Files
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src/backend/jit/llvm/llvmjit.c | 2 ++
1 file changed, 2 insertions(+)