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Subject: Re: [PATCH v16 10/11] of: fdt: Add memory for devices by DT property
 "linux,usable-memory-range"
From:   "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>
To:     Rob Herring <robh@kernel.org>
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Date:   Thu, 9 Dec 2021 09:59:11 +0800
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On 2021/12/1 10:55, Leizhen (ThunderTown) wrote:
>>> +	}
>>>  
>>> -	memblock_cap_memory_range(cap_mem_addr, cap_mem_size);
>>> +	memblock_cap_memory_range(rgn[0].base, rgn[0].size);
>>> +	for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++)
>> s/ &&/,/

Hi Rob:
  I want to keep "&&" unchanged, do you mind? I'm going to post an
updated version tomorrow, hopefully the last.

> Hi Rob:
> 
> The comma operator may not be suitable for logical judgment. The logical judgment
> before commas (,) is ignored.
> 
> Here's my test：
> 
> C code：
> int main()
> {
>         int i, j;
> 
>         printf("&&:\n");
>         for (i = 0, j = 0; i < 2 && j < 3; i++, j++)
>                 printf("i=%d, j=%d\n", i, j);
> 
>         printf("\ncomma:\n");
>         for (i = 0, j = 0; i < 2, j < 3; i++, j++)	//(i < 2） before comma is ignored
>                 printf("i=%d, j=%d\n", i, j);
> 
>         return 0;
> }
> 
> Output：
> &&:
> i=0, j=0
> i=1, j=1
> 
> comma:
> i=0, j=0
> i=1, j=1
> i=2, j=2
> 
>