pgsql: Don't lose precision for float fields of Nodes.

Don't lose precision for float fields of Nodes.

Historically we've been more worried about making the output of
float fields look pretty than whether they'd be read back exactly.
That won't work if we're to compare the read-back nodes for
equality, so switch to using the Ryu code for float output.

Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://www.postgresql.org/message-id/flat/4159834(dot)1657405226(at)sss(dot)pgh(dot)pa(dot)us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/acd624644bc4f957824abcd00f6af27861b03a29

Modified Files
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src/backend/nodes/gen_node_support.pl | 12 ++++++------
src/backend/nodes/outfuncs.c | 23 +++++++++++++++++++----
2 files changed, 25 insertions(+), 10 deletions(-)