Re: rawmemchr usage

[Bruno Haible]

Eric Blake wrote:

> +     strtok_r: use rawmemchr for speed.
> +     * lib/strtok_r.c (__rawmemchr): Use faster rawmemchr.
> +     * modules/strtok_r (Depends-on): Add rawmemchr.
> ...
> Likewise, what about these other modules that only use strchr to find the 
> terminating byte of a known-terminated string, where rawmemchr could be the 
> faster choice?
> 
> lib/argz.c:     entry = strchr (entry, '\0') + 1;
> lib/argz.in.h:  __entry = strchr (__entry, '\0') + 1;
> lib/canonicalize-lgpl.c:      dest = strchr (rpath, '\0');
> lib/canonicalize.c:      dest = strchr (rname, '\0');
> lib/glob.c:                 end_name = strchr (unescape, '\0');

This time I'm with Sam Steingold's argumentation: We should avoid creeping
additions of dependencies. rawmemchr is additional code to be compiled on
all non-glibc platforms, whereas strchr() is present in libc on all systems.
There is nothing wrong with the use of strchr(). I even doubt whether the
code in lib/rawmemchr.c can beat assembly language code like the one glibc
has for strchr. Furthermore, the code in lib/canonicalize*.c is certainly
not speed relevant (since it mostly makes system calls).

Bruno