From mboxrd@z Thu Jan  1 00:00:00 1970
From: Randy Dunlap <rdunlap@infradead.org>
Subject: warning: division by zero
Date: Tue, 13 Feb 2018 16:26:04 -0800
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In Linux kernel, we get that message 2 times (in x86_64 allmodconfig):

../fs/exofs/ore_raid.c:95:64: warning: division by zero
../fs/exofs/ore_raid.c:116:36: warning: division by zero

when dividing by variable sizeof_a1pa, where that is:
	const unsigned sizeof__a1pa = sizeof(_aab->__a1pa[0]);

which is in this struct:
	struct _alloc_all_bytes {
		struct __alloc_stripe_pages_2d {
			struct __stripe_pages_2d sp2d;
			struct __1_page_stripe _1p_stripes[pages_in_unit];
		} __asp2d;
		struct __alloc_1p_arrays {
			struct page *pages[group_width];
			struct page *scribble[group_width];
			char page_is_read[data_devs];
		} __a1pa[pages_in_unit];
	} *_aab;

where 'pages_in_unit' is a function parameter. So, yes, it could have a value
of zero.

Is the warning message considered correct or useful as is?  If so, OK, no problem.
Although I would rather see something more like:
	warning: variable length array on stack

thanks,
-- 
~Randy