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5028f22f6e
The old algorithm was found to not be the usual CRC-32 algorithm, used by Ethernet et al. We were using a non-reflected lookup table with code meant for a reflected lookup table. That's a strange combination that AFAICS does not correspond to any bit-wise CRC calculation, which makes it difficult to reason about its properties. Although it has worked well in practice, seems safer to use a well-known algorithm. Since we're changing the algorithm anyway, we might as well choose a different polynomial. The Castagnoli polynomial has better error-correcting properties than the traditional CRC-32 polynomial, even if we had implemented it correctly. Another reason for picking that is that some new CPUs have hardware support for calculating CRC-32C, but not CRC-32, let alone our strange variant of it. This patch doesn't add any support for such hardware, but a future patch could now do that. The old algorithm is kept around for tsquery and pg_trgm, which use the values in indexes that need to remain compatible so that pg_upgrade works. While we're at it, share the old lookup table for CRC-32 calculation between hstore, ltree and core. They all use the same table, so might as well.
25 lines
582 B
Makefile
25 lines
582 B
Makefile
# contrib/hstore/Makefile
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MODULE_big = hstore
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OBJS = hstore_io.o hstore_op.o hstore_gist.o hstore_gin.o hstore_compat.o \
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$(WIN32RES)
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EXTENSION = hstore
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DATA = hstore--1.3.sql hstore--1.2--1.3.sql \
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hstore--1.1--1.2.sql hstore--1.0--1.1.sql \
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hstore--unpackaged--1.0.sql
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PGFILEDESC = "hstore - key/value pair data type"
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REGRESS = hstore
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ifdef USE_PGXS
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PG_CONFIG = pg_config
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PGXS := $(shell $(PG_CONFIG) --pgxs)
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include $(PGXS)
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else
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subdir = contrib/hstore
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top_builddir = ../..
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include $(top_builddir)/src/Makefile.global
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include $(top_srcdir)/contrib/contrib-global.mk
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endif
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