From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH] eal/arm64: fix memory barrier macros
Date: Tue, 16 Jan 2018 01:21:28 +0100
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References: <20180115235934.16054-1-thomas@monjalon.net>
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Cc: jerin.jacob@caviumnetworks.com, jia.he@hxt-semitech.com
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16/01/2018 00:59, Thomas Monjalon:
> The macros dsb and dmb are defined as an instruction block with braces.
> As a consequence, when it is used in if/else without brace:
> 	if (cond)
> 		rte_mb();
> 	else
> 		statement;
> the added semicolon is parsed outside of if/else,
> so the "else" cannot match the "if":
> 	if (cond) {
> 		asm volatile("dsb sy" : : : "memory");
> 	}
> 	;
> 	else
> 		statement
> 
> The solution is either to use the "do { } while (0)" construct,
> or simply remove the braces because there is only one statement.
> 
> Fixes: 84733fd0d75e ("eal/arm64: fix memory barrier definition")

Just seen there is already a patch doing the same thing by Jia He:
	https://dpdk.org/patch/31896
This patch is in a series waiting for required changes.