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Message-ID: <CAOj2s=QtQW_BO3EF-cnYVXNMvXLDQ6zQ=iU_+dO9wr0Yu7QF1Q@mail.gmail.com>
Date: Thu, 25 Aug 2016 09:47:06 +0200
From: Per Johansson <per@...th.org>
To: musl@...ts.openwall.com
Subject: syslog.h prioritynames define not compatible with -Wwrite-strings

Hello,

I'm trying to port a code base to musl. I've run into an issue with
prioritynames as defined by syslog.h:

CODE *pri_code = prioritynames;

produces

error: initialization discards 'const' qualifier from pointer target
type [-Werror=discarded-qualifiers]

This is repeated once per element in the array.

While the error message points to -Wdiscarded-qualifiers I believe
this is actually due to us using -Wwrite-strings which turns string
literals into type const char* instead of char*.

I suppose the most compatible solution would be to cast each string
literal to char* in the define. It's either that or use const char* in
the struct, but that's likely to cause issues in other programs.
Or use some trickery to disable the warning I suppose, wouldn't know about that.

Please CC me on any reply as I'm currently not subscribed.

Minimal code to reproduce:

#define SYSLOG_NAMES
#include <syslog.h>
CODE *c = prioritynames;

Compiles without warning:
gcc -nostdinc -isystem include -isystem obj/include -c test.c

Adding -Wwrite-strings give warnings:
gcc -Wwrite-strings -nostdinc -isystem include -isystem obj/include -c test.c

Regards,
-- 
Per Johansson

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