Incorrect overflow check condition for WAL segment size

Hi all,

Although we restrict the WAL segment size to 64 MB as upper limit, the
following piece of code in guc.c (line 715) seems confusing to me.

#if XLOG_SEG_SIZE < (1024*1024) || XLOG_BLCKSZ > (1024*1024*1024)
#error XLOG_SEG_SIZE must be between 1MB and 1GB
#endif

Either the comment is wrongly written or the check for overflow
condition has to be fixed. Assuming the overflow check condition to be
erroneous, I've attached a patch to fix this.

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Thanks & Regards,
Kuntal Ghosh
EnterpriseDB: http://www.enterprisedb.com