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Date: Thu, 07 Mar 2019 23:40:00 -0000
From: Zoltan Kocsi <zoltan@bendor.com.au>
To: gcc@gcc.gnu.org
Subject: Signed-unsigned comparison question
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Gcc 8.2.0 (arm-none-eabi) throws a warning on the following construct:

uint32_t a;
uint16_t b;

if ( a > b ) ...

compaining that a signed integer is compared against an unsigned.
Of course, it is correct, as 'b' was promoted to int.

But shouldn't it be smart enough to know that (int) b is restricted to
the range of [0,65535] which it can safely compare against the range of
[0,0xffffffffu]?

Thanks,

Zoltan