pgsql: Adjust MemSet macro to use size_t rather than long

Adjust MemSet macro to use size_t rather than long

Likewise for MemSetAligned.

"long" wasn't the most suitable type for these macros as with MSVC in
64-bit builds, sizeof(long) == 4, which is narrower than the processor's
word size, therefore these macros had to perform twice as many loops as
they otherwise might.

Author: David Rowley <dgrowleyml(at)gmail(dot)com>
Reviewed-by: Heikki Linnakangas <hlinnaka(at)iki(dot)fi>
Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Discussion: https://postgr.es/m/CAApHDvoGFjSA3aNyVQ3ivbyc4ST=CC5L-_VjEUQ92HbE2Cxovg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/586d63214e369283472b5c03fdbaf59833209b3e

Modified Files
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src/include/c.h | 38 +++++++++++++++++++-------------------
1 file changed, 19 insertions(+), 19 deletions(-)