Don't call fwrite() with len == 0 when writing out relcache init file.
Noticed via -fsanitize=undefined.
Backpatch to all branches, for the same reasons as 46ab07ffda9.
Discussion: https://postgr.es/m/20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de
Backpatch: 10-
Branch
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REL_10_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/5f4615b9def5c7a4218c7e17f318e4b2eb2b1747
Modified Files
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src/backend/utils/cache/relcache.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)