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Re: [GLIBC][PATCH v2] Remove strdup inlines
On 12/12/2016 06:11 PM, Joseph Myers wrote:
> On Mon, 12 Dec 2016, Wilco Dijkstra wrote:
>
>> this is premature micro optimization. Removing unnecessary string copies
>> (why is strdup of a constant string a useful idiom that should be optimized?)
>
> It's useful to strdup constant strings e.g. to ensure that a string in a
> given context is always dynamically allocated, so that subsequent code can
> free it without needing to know where that particular value came from at
> runtime (if some code paths use a constant value, others use a value from
> elsewhere). (That doesn't answer why it would be performance-relevant.)
Exactly. The only relevant use of strdup I have ever added to glibc is in
the ld.so.cache processing in dlopen to ensure that reetrant dlopen calls
can rely on their cached copies being unique (strdup'd) and freeable.
--
Cheers,
Carlos.