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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 21 Dec 2018 14:29:30 -0800
Message-ID: <CAHk-=whLFsxr751LsJoxe-E=4LVvh=hB-3MmQTLVRA5mMLHzJA@mail.gmail.com>
Subject: Re: [for-next][PATCH 23/24] string.h: Add strncmp_prefix() helper macro
To:     Joe Perches <joe@perches.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Andreas Schwab <schwab@linux-m68k.org>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Tom Zanussi <zanussi@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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On Fri, Dec 21, 2018 at 2:20 PM Joe Perches <joe@perches.com> wrote:
>
> Using
>
> static inline bool str_has_prefix(const char *str, const char prefix[])
> {
>         return !strncmp(str, prefix, strlen(prefix));
> }
>
> eliminates the strlen with gcc 4.8 (oldest I still have)

Ok, that looks like the right thing to do.

Side note: in the kernel we disable the whole "unsigned vs signed"
pointer warning entirely, exactly because of the "char *" vs "unsigned
char *" problem.

                 Linus